abèy MiMo IP may transceiver

K: I need to cover a 600 km circle area including mountains, hells means a total BLOS data link is required for that. Please send me all the kit for this structure design.

Vcan1988-2X2W supports 50km+, Vcan1988-2X5W supports 150km+ and Vcan1988-2X20W support 300km+.

K: Pa gen, only one drone in the sky, and the other 5 transceiver units at the ground.

If your needs are as described in the picture above, this network does not need to be a MESH network. You can set the drone node as the central node and other ground control stations as access nodes, which can save costs and achieve your needs.

K: Pa gen, what I need is. An airplane (a transmitter) is in the sky. 4~5 relay nodes are placed on the top of the mountain. There is only one ground control station (a receiver) at the bottom of the hill.

Based on your description, I drew a new diagram.
If this is the case, the MESH version is still needed, because every station on the ground can serve as a relay, ensuring that the signal is not interrupted even if the GCS is moved to another place.