i think being half-beastman in twst can go one of two ways
(obligatory disclaimer: this is all headcanon lol)
way one is the child having some or all of the beastman parent's features—tails, paws, ears, feathers, etc. example: vil, having a peafowl's crest and train, though no wings or talons (for feet anyway; his nails are notably stronger than a full human's).
way two is the child not having any notable animal features. example: deuce, not having bunny ears, tail, or paws (and thank the seven for that, ace would tease him so much). he does have big feet and strong legs though, which is part of why he's such a good runner. he's a beast (pun intended) on the track and field team for a reason. like, his legs are enviable. vil probably did a double take first time she saw him in basketball shorts or something during b5.
(she's a runner she's a track star– /lyr)
this isn't to say that they can't have their beastman parent's facial features that may be influenced by their animalistic heritage. deuce has a very strong literal bunny face, with a flat nose, round face, and large eyes (which makes him look very cute and innocent, so when he goes delinquent mode, it's even more jarring), so he looks basically identical to dylla. vil also has his mother's nose, though she looks like eric in most other regards.
anyway vil and deuce both look like their moms. vil doesn't know it, and doesn't particularly care, since he obviously doesn't know her mother, and he frankly does also resemble eric quite a bit, if not more than she resembles adelaide. deuce though. deuce looks just like mama and he loves it. he looks absolutely nothing like his father and both he and dylla are so glad about it.
