Think Pep is done with full-backs. And I don't blame him.
At this stage, most full-backs that people consider great are defensive liabilities. No coincidence that the only one left at City is Walker, one of the very few who is a genuinely fantastic defender. Zinchenko, Cancelo, Mendy - these guys consistently are the weakest defenders in the squad because football is finally catching up to the fact that asking players to be great attackers and great defenders is just asking far too much of 95% of them. Even elite fullbacks like Davies and Alexander-Arnold are not nearly good enough defensively.
And with Pep leaning more and more towards full-backs that play in midfield, I think he's finally decided just to commit to three centre-backs and two DMs and do away with the full-back position entirely.
But it's Pep, so there's a good chance that in ten years all the big clubs will be doing the same. Young full-backs like Lewis who can move into midfield will be fine, but guys like Lamptey and Livramento are in trouble.