The goal Liverpool scored appears to be fine. It is amazing control from Lallana if he intends that pass for Mane with his shoulder, incredible skill, but it is not off his arm. Not sure why Wolves are unhappy about that. There's no evidence of a handball from any players.
The offside system is the annoying one because VAR cannot be so accurate with offsides. The images are not sharp enough and there aren't enough frames to capture an image from the precise moment the ball is played in order to draw the lines on. Somehow, some tolerance for errors needs to be built into that system. While I have sympathy with Wolves over the goal they therefore had chalked off, it's the same standard that VAR has applied for offsides all season. So the decisions VAR has made in this match would appear to be the correct ones.