I did this with my (mostly) OpenWrt-based network: https://github.com/kwesthaus/network-config.
I chose the NanoPi R4S instead of the R6S as my router since it is fully supported by vanilla OpenWrt [1] whereas the R6S is still in the works [2].
[1]: https://openwrt.org/toh/friendlyarm/nanopi_r4s_v1
[2]: https://forum.openwrt.org/t/nanopi-r6s-a-rockchip-rk3588s-ro...