[Mesh] Low power options for small robots

Hi All, Finally getting some time back to tinker and build my own projects and was hoping for some advice on low power mesh networking. I grabbed 2 of these small USB powered hotspot/bridge/etc GL.iNET GL-MT300N-V2 units (little, yellow, different) for ad hoc networking of robot(s) but haven't started putting things together yet, figured this would be the place to ask. Any ideas on flashing these with something open source or privacy red flags w/ this vendor? Will they work with sudomesh firmware? Most likely will be powering with solar and connecting to a RPi w/ a patch cable then talking to eachother, either 2 rovers or a rover and a quadcopter for initial test. If y'all have already perfected the tiny lora boxes I will try to build something around those. Cheers, Hol