A Youtube Buddy
Check out Archwiki plymouth , in the installation section, make sure that you have silent boot as that’s what usually blocks plymouth from displaying.
If I understand your query correctly, Fedora uses a Plymouth theme called bgrt which displays the OEM logo and asks for the key in a nicer input. Try setting your Plymouth theme to bgrt
bgrt
Check out Archwiki plymouth , in the installation section, make sure that you have silent boot as that’s what usually blocks plymouth from displaying.