Ubiquiti USW-Flex-XG switch
"This worked just as planned. I have a UDM-Pro that offers 10GbE via an SFP port. I have a 24 port Unifi Switch that only offers 1GbE, whether by SFP or standard port. I used the USW-Flex-XG as an aggregation switch. It connects via 10GbE SFP to the UBM-Pro and to the 24 port switch over a link aggregation pair of 1GbE ports going to a pair of SFP ports on the switch. That gives a 2GbE link from the UDM-Pro to the 24 port switch. It also has a port to spare if I get another 10GbE device. The option to do a link aggregation pair on the UDM Pro right to the 24 port switch is not available because the 8 copper ports on the UBM-Pro share a single 1GbE connection to the CPU of the UDM-Pro. So 2 bonded ports still could not exceed 1GbE."