That is a very common workflow. Usually, this means sound editorial will do a conform. Pro Tools has an ‘expand tracks’ option which can do a multichannel conform from single channel cuts in a timeline (you hand them your cut as AAF plus media, they ingest ALL original BWF files with all tracks, they can make PT link any event to all matching tracks).
Alternatively, some sound editors prefer to use external applications like Virtual Katy, Conformalizer or EdiLoad. In that case, you may need to hand them over a sound EDL on top of your ‘normal’ export.