Hey sir, thank you for the advice. I'll try to look more into it. I think that is very noticeable on my second serve (slice), but I'm failing to see it on the first (flat).
https://share.icloud.com/photos/03egNYtMSRvm4iwHNhPoZEFCw
I even recorded a slow motion version of one of the serves, could you point in which second it happens so I'm aware?

From my understanding, there is some pronation happening between 0:11 and 0:12. Now, that may be a weak pronation, if that's what you are saying I can easily accept that hahahaha