Recommending small 2.4GHz client -> ethernet client with external antenna?

Hi, I am looking for a very small 2.4GHz client -> ethernet board (preferrably capable to run OpenWRT) with connector for external antenna. The device should have a good low noise wireless amplifier, would be used for point-to-point with directional antennas on both ends.

Any power supply method (POE, direct connector).

Sth like the board of Ubiquiti PicoStation M2 which has been out of production for long. Could be some small chinese OEM board with good recommendations too.

The use case is an industrial tablet with external antenna, communicating with 100m max outdoor directional AP hooked to an IP camera. Direct sight of view gets sometimes slightly hindered (i.e. 5GHz+ not usable). RTP video stream 4Mbps max. Every dropped packet in the UDP stream is directly visible, the goal is to minimized dropped packets. The integrated wifi interface of the tablet has poor sensitivity and quality. The tablet has a decent ethernet interface, no video artefacts over the 100Mbps ethernet.

IIUC the best technology would be the 802.11ah band (like ) but the HaLow specs in Europe do not allow higher bitrates.

Thanks a lot in advance for any suggestions and hints.