If a PL club enters an insolvency event then all sorts of sanctions kick in one of which would be the club not being able to ( save some exceptional circumstances) register players.Similarly if a disciplinary hearing is about how a player was signed then the IC can rule that the specific player cant be registered but other than that the PL disciplinary sanctions don’t include the ability to sanction a club by way of a transfer embargo.However, don't they have to agree the 25 player squad that we submit after each window? It'd be easy to say 'you can't play him'
The league would be open to a challenge ( which they would lose) if the tried to stop a club registering a player and then including them on the squad list if they were signed in accord with PL & FIFA rules / regulations