The lounge access for FJ and certain OW FFP is posted in the dedicated thread:
https://www.flyertalk.com/forum/30507350-post94.html (I assume it's still valid)
For BAEC status, unless you are flying on BA codeshare on FJ out of NAN, or BA codeshare on FJ out of SIN, you don't have lounge access solely based on status. It's so complex that even though FJ is now a OW connect partner, you may treat as if it is not in OW.