The only viable sch to gbr conversion we know about at this time, is potential export between two PCB / gerber formats. Both .sch and .gbr files are a bit generic and probably used in several tools, so it may be possible that more than single variant of this conversion exist.
Your best option in this case is to use one of the dedicated gerber software, because it is extremely unlikely that you will find something like simple schematics to gerber converter.
Updated: January 5, 2024