I made a small remix of tksgeos PAC-MAN's Ghosts to attach the backplate with magnets. I only included the remixed parts. You can find the rest of the parts and print instructions here.
You'll need 8 magnets with 10mm diameter and 1mm height.
For the bodies, pause at 33.20mm to insert Magnets.
Fot the back cover pause at 2.00mm to insert Magnets.
The holes for the magnets are made with negative volumes. So if you want to use differently sized magnets, you can edit them easily in PrusaSlicer.
The author remixed this model.
Added structure to attach magnets.