A permanent Back 3, rather than his customary transitional ones? Probably not given the evidence at hand, but never say never; Cruyff played with a lot of
3—4—3 diamond base setups in his time as a coach, and ten Hag could be inspired by them.
As regards Timber, there's a historically significant convention of defenders transitioning into more center-of-the-pitch roles (and vice versa): Neeskens (fullback to midfielder), Rijkaard (stopper to midfielder), Breitner (fullback to midfielder), Júnior (fullback to midfielder), Desailly (stopper to midfielder at Milan), Fabinho (fullback to midfielder), at times even de Jong featured as a central defender with de Ligt. This lad could potentially trend along similar lines too, given his technical level, maneuverability/dynamism in tight-ish spaces, obvious footballing intelligence and the fact that he does not mind putting in the legwork. While relatively short central defenders can be successful to varying degrees (from meh like Ben White and Nathan Aké to imperious like Fabio Cannavaro and Roberto Ayala), he has some attestable fragilities in the air (which could be magnified and exploited in the Premier League, vis-à-vis the Eredivisie or Europe):
That being said, what he brings to the table as a ferocious Swiss army knife type of central defender (especially in a possession-focused team than employs an aggressively high defensive line) is undoubtedly more
special and peculiar and valuable than what he would bring to the table as a midfielder — and if successful in the former role, he could emerge as a reference point and minor trend-setter in the Premier League and open the door for more vertically challenged central defenders (as there's a lot of monkey see, monkey do escalation and general destigmatization in the quest for success/relevance). For that possibility alone, we should probably persist with him as a central defender through the early goings (if we sign him, of course).