Can I change EFI folder contents without reinstalling macOS Catalina?

So, the scenario is I have a okayishly working EFI/OC setup. Which works fine but has got some minor issues for which I wish to check with some kext and smbios changes.

So, if I install macOS from the recovery USB as suggested by the Dortania Guides and later change a few things in the EFI folder specifically kexts and whatever additional changes those require and SMBios.

Once, I am sure/satisfied with a specific complete EFI setup I plan to finalize the files in post install ways.

Thanks in advance and sorry if I am creating confusion.