My experience with an Edgerouter X (and previously an Edgerouter 3 Lite) is that I found both routers (now and again, but frequent enough) did not play nicely with the Grandstream GWN7610's (or vice-versa).

I have to re-start the ER-X and/or the GWN-7610's (I mostly did both as I never came to a conclusion as to which was the problem).

2 x GWN-7610 are connected via ethernet (one to the upstairs Study and one traversing the Garage ceiling so that it was closer to the inside of the house [but I think a waste of time]) and one via mesh.

I have, over the years, tried to find out whether there was any discussion on this on the web i.e. Edgerouters and GWN7610's.

I want to upgrade to Wi-fi 6 and because I am with Spark and (very importantly) I want my wife to get support from Spark should I not be able to solve any issues with the equipment in the future.

1. If I went with a Spark Modem 3 and Spark Mesh 2, can I continue to use one or more of my GWN-7610's?

2. Could I use the ER-X as a switch? Searching the web, I don't understand the lingo (Level 2, Level 3 switch). So, could I just connect an ethernet cable from a LAN port on the Spark Modem 3 to a LAN port on the ER-X?

The ONT and ER-X are in the garage (and there is zero possibility that we will lay a new ethernet cable to the 'centre' of a two storey house as we want to move to a smaller house in the future (un-determined). We had one of the Ethernet cables (Cat 6 outdoor shielded) go from the garage to the upstairs study and connects to a ceiling mounted GWN-7610.