I know exactly the situation you’re suggestion and no Roon doesn’t support it.
I think it’s fair to say that playlist support in Roon is poor. I’m sure there are good reasons, but proper playlist support feels like an area ripe for development.
In the case you highlight. If your .csv playlist included the track, artist, album and year (common values you’d find in most generic exports) it should be ‘fairly’ easy for Roon to find a match in your local library with a high degree of confidence - that’s what Soundiz do when you ask it to migrate a playlist. You’d then need a setting to tell Roon what version of the matched track to add to the playlist ie. primary version / local version if available / highest quality.
My guess is there’s a concern that poor matches, even if almost all were accurate, could end up flooding the forum with complaints and well, who wants to launch a new feature if it risks driving up your support burden & an appearance of customer dissatisfaction. Dammed if you do, dammed if you don’t!
Maybe open a new feature request, this feels like quite a clearly defined use-case, or add your voice to an existing one.
These are a couple of the key playlist threads, the first going back to 2016.
This FR is a variation on your question, but is related more to playlists you’ve already imported into Roon via Tidal/Qobuz and then want to
migrate to local tracks if they exist.