I’ve been typing on this forum too much so I’m kinda lazy, I’ll write a bit.
He is closest in similarity to Bernardo Silva.
A maestro with the ball, doesn’t lose it, but can also glide past players pretty easily. Yet has an engine to run for days and help the defence.
He links the attack from the defence, so while he doesn’t huge goals and assists, he still gets quite a bit for what his role requires.
Barella just in serie had 12, then year before 14 goal contributions in the league alone.
These are such rare qualities in football, the complete midfielder who controls the ball well, dribbles well, defends and runs a lot, and chips in with goals and assists to boot.
He is everything on why I rate Bernardo Silva so highly.
You can look at his fbref stats (I’m too lazy) to see how complete he is.