Antony IMO can be an effective backup RW for us in situations where we're defending a lead and we need that extra defensive tenacity to close things down. As for an attacking threat, however, there isn't much there apart from, as you note, a good first touch, close control and an eye for a pass. But he has not shown any ability to break down a back line either with dribbling or defending. He's ghosted in for a few goals but it's a rare occasion when he's in the right place at the right time for a tap in.
Assuming we sell Sancho and don't bring in Olise, I'd be very comfortable with Amad being our first choice at RW and Antony as his backup. There's no point wringing our hands over the obscene transfer fee (30m over what Ajax was originally asking for, I believe) for a mediocre footballer and he's virtually unsellable at any price but as cover for Amad I think he can do a job for us.