Station mode as Layer 2 Bridge?

[Josephny]

I found the "crutch:"

Station Pseudobridge not working with hAP ax2 and hAP ax3

Oh but THAT does not work. You need to use same wifi technology on both sides !

But:

The main environment's AP is a Unify LR7, and I can't start messing with it.

I was hoping for a simple solutions.

Thank you for clarifying for me that the L2 bridge between the cAP's wifi and ethernet interfaces is not the problem; rather, making an L2 bridge between the cAP and the main AP (with wifi being the hardware/link level connection) being the problem.