Maybe, I can upload a Softemu mod with a PAL bios for you to try 576p with
https://www.psx-place.com/resources/lbfn-with-updated-libcdvd.971/
it has various video modes like VGA, VESA as well as a nice bilinear filter to sharpen the text.
I have no way of testing it myself though, since i'm on a later CFW.
If we can dump the DEX keystore mechacon-keystore.bin of Netemu we might be able to trigger some update.
In Softemu the DVDPlayer update is blocked but FMCB still works, you can reactivate the DVDPlayer update by redirecting the missing ROM1 paths to the memory card update, it's a small fix if someone wants to update osdmenu.
Hacking the mechacon also is suppposed to reactivate iLink & host, I think an earlier Softemu build had network support for debugging, idk.
All i've done atm is edit the SCPH name string in the nvm file.