sure, that’l work.
however…
i’d say wait till you’re done editing till you do this, as you wont get any RT with a non-standadrd sequence size.
and if you render as you go, it; would be pretty simple to export it as-is,
and then run that through compressor, using it;s cropping function in the Geometry tab.
it;s simple, and probably faster than FCP.
you dot have to drop the quality at all, just use a Prores codec, even the same one you’ve been cutting with.
i’d also say that “2.35” is not a common ratio these days, even though it’s a common TERM.
the ratio we’ve been delivering lately is 2.40:1
also, who or what are you making this for?
find out what you actually need to deliver.
cheers,
nick