We had this lately discussed, that it would need a ca. 2mb big partition if it is legacy boot. And then this partition should have the boot flag, as I remember ?! Talk: Fedora 42 Workstation installer doesn’t support Fedora re-installation on MBR disks | MBR to GPT - #8 by vekruse
There is also a Change Request that all Installations with EFI should just have a GPT instead of a MBR DosBoot record . to work with the new Anaconda installer.