It’s what William Tell was, more roguish! (6)
I believe the answer is:
archer
'was more roguish' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for archer that I've seen before include "Arrows one sends" , "Bowman - popular author" , "His weapon is the bow" , "One uses bow and 30ac" , "A bow-and-arrow man" .)