I use the 'use option as meta' heavily and haven't till date needed to type accented chars. Maybe you can try to use only the left option as a meta and leave th

I use the 'use option as meta' heavily and haven't till date needed to type accented chars. Maybe you can try to use only the left option as a meta and leave the right one for accented chars? Not sure whether the Terminal.app supports it, better chances of iTerm supporting it though.