@Pancake-Cookie oh hey!
This dinner sounds like such a sweet thing to do with your friends, I wish I could be there! I think you should definitely introduce them so they can at the very least be friends- I know what it's like to have so few friends in a new country, so you're definitely doing a service to them!
As for setting them up romantically, I might chill out on that one for now. If A came out as pan recently, she might need some time to accept herself and get a little more footing in her sexuality before diving right into a queer relationship. And if A doesn't know that Smiley is a lesbian, you might want to wait for Smiley to tell her herself just in case that's not info she wants everyone to know.
Plus, if you haven't asked either friend how they feel about being set up/if they're looking for help finding a partner, they might feel a little blindsided by the situation. For now, just go into it with platonic energy, and if they hit it off, they hit it off and you can offer to set up more group hangouts like this so they can continue to get to know each other within their comfort zones!