Thank you, so I will check if those screens can work without I2S (did you mean I2C?). Unfortunately I am afraid the screens I had in mind wouldn’t work:
HyperPixel 4.0 uses literally all of the GPIO pins on the Raspberry Pi, including the standard I2C pins (BCM 2 and 3), but we’ve broken out pins BCM 10 and 11 as well as 3V3 power and ground, so that you can use I2C devices at the same time as using your HyperPixel 4.0.
Can you confirm?
I am not sure about the IO voltage either. You said it is 1.8V but that seems to differ from what is in the wiki here: Accessing 40-pin GPIO | Seeed Studio Wiki
Also, for screens that would not require I2S (or I2C?), would it work before the OS is booted (BIOS, LUKS encryption passphrase)? I have no experience with the Pi pins and never used them so far.