I don't think that makes much sense at this point. Surely if we buy another CB now it has to be someone who is better then every CB at the club. If we buy Maguire to sell Smalling and Jones just so Lindelof gets to play, we are not strengthening the squad.
Maguire would first be an upgrade on Lindelof and Rojo if anything and if Tuanzebe plans to be our CB he should be fighting off bigger challengers than the likes of Maguire, Lindelof and Rojo. I think he is good tho, but he seems a bit overrated here right now, and i don't see a big reason to get him. Ok, it seems tempting to maybe replace Jones and Rojo with him and another top defender, but buying 3rd defender shouldn't be priority right now
I personally don't see a need for a top cb let alone buying any more CBS for that matter. Bailly is going to be top class. So is Lindeloff. Tuanzebe has the potential to be and Smalling, Jones, Rojo and blind are excellent cover. If we were at all to let the Smalling's go I see zero reason to buy a starting cb. That is where a Maguire then makes sense because a squad always needs good competition/cover. Even then I'd rather give that role to Fosu Mensah. People on here seem to constantly overlook the fact defence is by far our strongest department in our first team.
You can't have Valencia, Young, Bailly, Smalling, Jones, Rojo, Shaw, Blind as your senior men with Riley, Fosu-Mensah, Tuanzebe, Williams, Borthwick-Jackson and Mitchell as the talent under them and you still say you need more defenders.