I have to second u/RedFive1976 about the importance of outdoor-rated fiber between structures, especially if the unshielded Ethernet cable is parallel to the power line running out to the barn. The elimination of EMI-related attenuation alone makes the switch worth it.

I recommend a managed switch to place devices into VLANs (IoT, cameras, PCs, etc).

I use the TP-Link Omada infrastructure at home.

What you want in this case is a WiFi point-to-point bridge.