Hi Thomas!
I believe there are many ways to say that. In Argentina, apart from "reunirse (con alguien)", it's very common to hear the verbs "encontrarse" or "juntarse". For example: "Me encontré con Juan a tomar un café".
Here's a translation of the sentences you mentioned:
- We meet for coffee = Nos juntamos a tomar un café.
- Me and my friends meet every week = Mis amigas/os y yo nos juntamos cada semana.
Hope that helps!