I think Gabriel Jesus and Kai Havertz should be on the selling list because both of them can't make enough contributions so that the funds can be used to sign a new clinical striker. If Arsenal plans to bring in Nico Williams and even Zubimendi then Arsenal will have to sell more players or another option is to release big players to get big fresh funds, which means there is a possibility that Saliba will leave Arsenal because there are rumors, that Real Madrid are very interested in signing Saliba, and they also seemed willing to pay a lot for him.
Saliba strongly linked to the Real Madrid's move, but he has denied it. He said he's willing to play even longer at Arsenal. I know he can change his mind anytime, but it seems this rumor won't happen.
His club is not also keen to sell him, and forced him stays for another year. However, we can also expect him to turned things around when his club leave from UCL soon.