"The most immediate development priorities are likely to be: ... More simulation content"
Is co-crossdressing possible? I hope so.
Viewing post in Course of Temptation "What Cums Next" Update (v0.8.0) comments
You could look at it a different way, and say that because clothing isn't gendered in this game, (co-)crossdressing is technically possible (though the co- part of it might be heavily dependent on RNG), and nobody will even judge you for it. Perhaps a better question might have been something about managing the wardrobe of a partner.