If you can’t find a custom ROM, you could try a GSI. iodéOS has one and it should theoretically work on an S23 FE, though the installation process will be slightly different because I believe you need to use Heimdall to flash third party firmware on Samsung devices. It’s not guaranteed everything will work smoothly with a GSI either, you may need to play around with the settings once installation is complete.
If you can’t find a custom ROM, you could try a GSI. iodéOS has one and it should theoretically work on an S23 FE, though the installation process will be slightly different because I believe you need to use Heimdall to flash third party firmware on Samsung devices. It’s not guaranteed everything will work smoothly with a GSI either, you may need to play around with the settings once installation is complete.
Nope. The three other S23 models have a GSI, but not the FE model.