hello markTT
I don’t think the Zyxel AX7501-B1 supports link aggregation on the LAN ports.
According to the specs sheet of the AX7501, there are 4 Lan Ports with 2.5GBit/s and one Port with 10Gbit/s.
I am not sure if Sunrise will allow bridge mode on a fibre connection.
Depending on what you try to do and how your network should look like, you have the option to connect a L2 or L3 switch to the 10Gbit/s port. If you don’t plan to use VLANs or you don’t really have much traffic between VLANs L2 switches would work perfectly well. If you depend on high speed between devices on different VLANs, a L3 switch might be the choice.
I don’t have a fast internet connection, but my network is setup to handle 2.5Gbit/s localy. I am using the XMG1915-series switches from Zyxel. They are L2-switches, traffic on the same VLAN is always at max speed. But traffic between VLANs is slow. It’s because my router slows down the speed a lot.