Looking for a good OpenWrt-capable router with WiFi 6/7 which works well with Roon

I am looking for a new broadband router for my small home: 2-storey, most Roon stuff on Ethernet wiring but 1-2 speakers on WiFi connections (longest WiFi distance to router: 7.6m through a concrete slap + 2 thin walls).

I would like a router which:

  • Has 1 WAN port (for the broadband connection)
  • Has 3-4 LAN ports
  • Speaks WiFi 6, or even 7
  • Can be flashed with OpenWrt

Any idea for a good model or even some good Roon experience with one?