It's bizarre. I've found recently that my flirting game in a recently acquired language of mine (Dutch) is miles better than my English game.

There's never an awkward silence with Dutch. Asking simple questions that further the conversation, and making flirty comments about her personality or style or whatever seems more natural.

I think it mostly has to do with having 0 nerves about how things sound, since I'm not really good enough to fully understand those nuances perfectly. It makes it so that I end up not giving a fuck about what I say, which is better for flirting in most cases anyway!