Just a few skill ideas
You have some interesting ideas here and I like how you have tried to think of something unique, especially Assassinate. However things like scapegoat would have to be at 25% health as doing it at 1% would not work. I really love Disorientation however that is extremely OP. 3 stacks to nearby foes on stealth is too much. Would have to be 1 stack to nearby foes whenever you stealth at the MAX.
Stifled screams is interesting but how would you be able to stomp them if they are stealthed?
With stifled screams I was imagining it’d be like you applied a stealth like buff to them, making it so their teammates can’t see them but you can, sort of like if you stealthed an ally. So basically both of you are invisible to your opponents.
I imagined scapegoat being the way it is so that you literally disappear and the opponent thinks they downed you when really you are backing up. It could apply some sort of invulnerability or be like A.E.D and activate once you take lethal damage, saving you from the damage and teleporting you back. Obviously if it activated when you still have like 20% hp it would be obvious the downed copy was not you. unless the person really wasn’t paying attention.
Would be fun for us, but you have to consider they are trying to make fun fights for everyone. The reason people have mini-seizures about stealth is it’s annoying to play against. Most of what you listed, while cool, would be REALLY annoying to fight against, so not likely to happen.