Could it be that this device here: (brickcom wvs-01ap, manual behind link)
https://manualzz.com/doc/2852538/brickcom-wvs-01ap
...could be used with for exaple m7wp microphone and blue iris? Price is decent 70€.
There's mic/line in and rj45 ports. Device itself is a server and if I got it right...