'dnsmasq' likely isn't going to handle it. I'd either run kea on another box, or see if you can get it to compile for LEDE/OpenWRT.
http://kea.isc.org/docs/kea-guide.html#dhcp4-subnet-selection
A simpler option would be to run a DHCP server on each of the VLANs since you don't have any overlap in IPv4 address space