I did some tests.
Wrath: this Sin Affix reduces Total DMG -50%. when I checked the Stat Page, it doesn’t look like it reduces DMG by 50%, but when I checked DMG against monsters, you can see the reduced DMG in effect.
Sloth: this Sin Affix reduces movement speed by -100%. although you can’t move, Vault, Teleport, and other ways of moving with Skills still work. Skills and affixes that increase your movement speed will also work, but they are added to the -100%. I did a test with 1 Point in Dexterity (+0.5% Movement Speed), which gives a -99.5% movement speed. it took about a minute before I could tell that I was moving . if your SDS Set Bonus isn’t active, then you would need a total of +100% movement speed to get your original movement speed back. even with just Dexterity 20 (+10% Movement Speed) I was still going pretty slow.
Sloth & Momentum: the Sloth Sin Affix is considered a Movement Speed Bonus, even though it is Negative. I tested this with just Sloth & Momentum (1), and the DMG went down from just having Sloth on the Equipment and then adding Momentum. I realized that I would need to spend a lot more Crystals & Dust to see if Sloth, Wrath, and Momentum (5) could get to Zero DMG, or close to Zero DMG, and I decided that someone else who is really interested could do the tests.
@DuDono since the DMG is going down in these tests, this would only make the monsters happy. also, seeing that Red Negative Movement Speed was kind of creepy. especially when I went to a Map and tested to see if I could move.
personally, I think using Sloth Sin Affix in a Build could be a good test of a players Crafting Skills of how to get around without being able to move. using Momentum would be a bad idea unless a player wanted to test their DMG Crafting Skills.