Top 3 Sidescraping Tanks For Each Tier (In my opinion)

I may be bias in this, as I have not played every tank I've put on the list. However, I try to be as accurate as possible, and have included reasons on why a tank was chosen by me, or not. Your experiences could vary. I'll start with tier 4, where there are actually tanks that can/bother to sidescrape.

Tier 4:

1. Valentine - 60mm sides with tracks reinforcement and a high alpha gun allow the valentine to sidescrape well.
2. DW2 - 50mm flat sides with fat tracks and a 5 cm gun with decent damage, as well as central turret placement, make this tank very nice in sidescraping spots.
3. B1/PzKpfw B2 - 60mm side armor plus troll turret armor and great reverse-sidescraping abilities due to front turret placement mean that this tank can sidescrape decently. However, the tracks don't cover most of the side and provide extra spaced armor like the DW2's tracks.

Why the Matilda wasn't included - the shape of the hull and the placement of the turret allows your opponents to shoot through either your shoulders when you expose a lot of your tank during regular sidescraping (front-mounted turret), or auto-pen your 20mm roof on your rear if you try to reverse sidescrape. Furthermore, you have a rather low alpha gun, meaning you can't really trade as effectively. The Matilda is more of an angling, slow-advancing tank like the Churchill III. You can still okay if you're holding a position by sidescraping, however.

Tier 5:

1. KV-220 - absolutely ridiculous 100mm side armor plus thick tracks as extra reinforcement. Very tough to break during sidescraping - even if your opponents rush at you to take a less-angled shot at your side, it's unlikely to go through. In fact, sidescraping at a shallower angle is good as it will bait more shots into bouncing and lessening the chance that your opponent will go for your potentially weaker turret.
2. KV-1 - 75mm side armor is good for its tier, plus thick tracks. The KV-1 definitely has enough firepower to fight back at close range with both its 122mm and 85mm guns.
3. KV-1S - 60mm side armor is good enough with combined with tracks, and the KV-1S has extra mobility to get out of the way quicker than the KV-1 when poking out to take a shot. Firepower is similar to the KV-1.

Churchill I not included? 63mm side armor is fine, but the tracks aren't covering it, and there is a bulging armor zone that you can penetrate located on both sides, plus a 50mm thick hatch area. The flat turret is also relatively vulnerable to shoot at during sidescraping.

Tier 6: 

1. T-150 - a powerful 107mm gun with 90mm side armor + tracks allows for excellent sidescraping. The shape of the turret with its near-autobounce cheeks also helps a lot.
2. Churchill VII - relatively weak gun, but with the 9.9 HD armor model buffs the Churchill VII no longer has to worry about guns penning the "toolboxes" on the sides (they were removed). Now with the flat 95mm sides (even with a 115mm portion!) the Churchill VII can sidescrape much better, and it has good turret armor.
3. Heavy Tank No. VI - decent alpha with slab shaped 80mm sides, perfect for sidescraping. The turret armor can take a beating easily.

The KV-85 was not included as there are "bumps" on the middle of each side under the turret allowing many tanks to penetrate the KV-85 even when one sidescrapes at an extreme angle. 60mm is nothing special for a tier 6 heavy's side armor, anyway.

Tier 7: 

1. KV-3 - a big intimidating 122mm gun plus a long slab-shaped side of 90mm thick armor plus huge tracks allow the KV-3 to sidescrape very well. The turret also has very strong sloped cheeks that are very hard to penetrate for most tier 7s and 8s.
2. T29/Black Prince - even though it only has 76mm side armor, the T29 has very large tracks, nearly impervious turret armor when sidescraping, and a hull design that has no shoulders that an enemy can sneak shots into. When done correctly, the T29 can become nigh-invincible while sidescraping due to the impervious turret cheeks. The Black Prince's armor configuration makes it almost perfect for sidescraping, but its low alpha gun brings it on par with the T29.
3. IS - Not the IS-2, the IS. The IS is fast to pop in and out of cover, has 90mm side armor plus tracks, and a 122mm gun with some serious alpha. Don't linger too long to take your shot though, as smarter enemies may aim for your hull shoulders and get somewhat easy penetrations. As long as you wiggle and maneuver your tank right, you can mostly prevent this. The IS-2(s) are not tied with the IS because their shoulders are slightly weaker - 90mm compared to IS with 100mm.

The Tiger I was not in the top 3 as 80mm side armor with no track reinforcement was merely average for the tier, and the armor zone the tracks are covering are only 60mm and will be exposed at a shallower angle than the top portion. The gun doesn't have as much alpha as the T29, KV-3, or IS even though it has great DPM.

Tier 8:

1. KV-4 - extremely thick 150mm sides with track reinforcement and no shoulders. The turret is centrally mounted, compared to the IS-3's more frontally mounted turret. The crazy thick sides can bounce huge amount of shells even at seemingly low angles, including a 45 degree angle.
2. T32 - same as T29, a shoulderless hull with very trolly tracks that almost completely cover the side, making up for otherwise thin 76mm side armor. The turret is not an option for an enemy to shoot at if the T32 is sidescraping or not.
3. IS-3 - powerful gun with huge alpha allowing for favorable trades. The side armor is average at 90mm, but the spaced armor skirts and tracks highly amplify the thickness. The turret is very tough and rounded on its cheeks - no competent player would aim there. Be careful of displaying your shoulders of your front hull, though.

The Tiger II was not included because it has neither the sheer side thickness of the KV-4, the invincible turret and trolly tracks of the T32, or the spaced armor and high alpha of the IS-3. The KV-5 was not included either due to the R2-D2 often sticking out while sidescraping, presenting an easy target. Also, its gun is often too feeble to effectively fight back.

Tier 9:

1. E-75 - perfectly shaped 120mm side armor is good for sidescraping, and the tank has no shoulder weakspots. The gun is very intimidating, due to the high alpha, and the turret can easily bounce shells. The rather decent 30 degrees of traverse speed also allow the E-75 to react quickly if an opponent tries to rush forward to get a shot.
2. ST-1 - has shoulders, but the shoulders are tough, and the turret is almost invincible outside of the teeny (yet very strong) cupola. 140mm of side armor is excellent enough to bounce any shot thrown at it, and the 440 alpha is good. The ST-1 was rated lower than the E-75 for sidescraping because of its shoulders, and the potential for taller tanks to shoot and overmatch through its hull roof armor.
3. WZ-111-1-4 - Side armor is only 90mm, but the tracks and spaced armor skirts are extremely trolly in absorbing shots. The turret is very difficult to penetrate as the small cupolas are difficult to pinpoint quickly and accurately as the WZ-111-1-4 pops in and out of cover. The gun has excellent 490 alpha, the same as the E-75.

The VK 4502 B was not included despite its rear mounted turret, as the 100mm side armor with no tracks reinforcement (for its upper half) is not good enough to deter many shots. Also, who needs to sidescrape in the VK 4502B when the front hull of the tank has better armor than tier 10 heavy tanks?

Tier 10: 

1. Maus - it should be pretty obvious. A rear mounted turret, good alpha, and most of all, side armor that many opponents struggle to penetrate with no angling.
2. IS-4 - very thick 160mm side armor with skirts and tracks, plus a very tough turret and a well-balanced gun.
3. E-100 - extremely high damage 15 cm gun combined with side armor covered with huge skirts and tracks. Ranked lower than the IS-4 due to the tendency for many opponents to just spam HEAT rounds through your turret cheeks as you poke out to shoot. The alpha mostly makes up for that, however.

The IS-7 was not in the top three because the front hull shoulders are often exposed while sidescraping and present an easy target for opponents to shoot down on. The IS-7 came very close to the other tanks, but ultimately I decided not to pick it because of the shoulder vulnerability combined with its low HP.

TL;DR: Pretty much every tank with at least acceptable side armor can utilize the sidescrape tactic, and it's excellent for defensive stances. This review focused on the most outstanding tanks using this tactic for each tier, but tanks that can sidescrape are obviously not limited to the top three lists that I have created.

Thanks for reading, guys. I hope I made it worth your time to read this giant wall of text. :P