His best spell here was that first season where he was genuinely excellent most games in a classic double pivot in front of a back 4 where we didn't press much and tended to sit in a mid block and he could rely on his physicality and reading of the game instead of having to play some higher tempo/more shuttling type role. Even at his peak he's always been a pretty shit ball carrier/dribbler and isn't some pint point progressive passer (has a good eye for a creative pass mind you).
But, disregarding that shitshow of a "system" we had last season, Amorim generally likes athletic runners with technique in the middle of the pitch. They need to be able to drive through the midfield with the ball and cover ground off of it, but don't necessarily have to be Toni Kroos in controlling/passing. It's why Ugarte worked so well under Amorim at Sporting, as he's pretty mobile and a relentless defensive player that is also quite comfortable carrying the ball through the middle but isn't a great passer ( and didn't have to be).
Obviously he's too old, and my appraisal was one of current Casemiro and not the player he used to be.