Meshcore prefers to rely on volunteer infrastructure, meshtastic is better at ad-hoc networks.

If your going to a concert or convention, Meshtastic would be the better system. If your at home trying to make a local network, Meshcore is the tool for you.

Right now the issue is that they both mostly use the same hardware and there isnt really a method of using both projects on the same device to utilize their best aspects, ya sorta just have to go with what everyone else uses.