I am facing the same issue. BG3 is unplayable for me due to eye-strain headaches.
This could be solved when controller support is added, assuming the UI and font would be scaled up (as they were in DOS and DOS2). Any word on when controller support might be added? I'm hoping not to miss all of Early Access.
As for a font mod, unfortunately the mod solution for DOS and DOS2 does not work for BG3: replacing the original font files with other font files that are renamed with the original names. Dear Larian, perhaps if you could make this solution work for us, we could make our own mod and take the problem off your hands.
The only solution I've found is manually increasing the font size -- editing each of the font files -- using Font Forge (as described
here for DOS2). One limitation of this solution is that it can't be shared as a mod.
