Reading your post here and your posts on other boards on this forum, I would suggest that you take a step back and take the time to analyse what you want to achieve.
If I can remember correctly from the other postings you currently have three separate internet connections with different providers which you explained that you needed as you required the resilience that set up supplies. However, none of the three providers supply kit that gives an adequate WiFi signal throughout your property.
There are other ways to provide the resilience in a less complicated manner but that would need you to decide that your existing set up is not the most efficient or optimal way to achieve your resilience goal. If you do decide to make that mental leap you would no longer need to spend your time worrying about which router you can connect to which network, which expensive bit of hardware to resource next etc. and you would also have the potential to reduce your monthly outgoings. Each to their own and you may well have other valid reasons to stay with your existing set up but at face value you seem to be over-complicating things to achieve what you want.
Edited by GonePostal (Mon 20-Feb-23 21:51:11)