Steam version launched Origin so everyone plays on the same servers.
I can't really tell as I'm not a big player of Titanfall 2 on PC (I'm a PS4 player when comes to Titanfall 2), but if I can assume freely, no since cross-lay appeared in APEX Legend a year post launch and I believe that was new to Respawn to develop it. Same goes with Titanfall which wasn't on Steam before APEX Legend if I recall right. The best place to ask would be in the Titanfall 2 forums though found here:
https://answers.ea.com/t5/Titanfall-2/bd-p/titanfall-2-technical-issues-en
You're currently in Titanfall 1's forums.
Don't take my word for it though, I really don't know and that's just my personal guest.
