Root is an asymetrical board game of factions trying to control a forest. It has a companion PbtA RPG based on the setting.

I think playing a session of the boardgame to set up the beginning state of the forest, and then running the RPG (with some Blades in the Dark faction tracking) would be fun.

Alternatively, run the RPG side with Mausritter. Make it more about delving into the deep woods and breaking into faction keeps.

In my experience the biggest problem with large groups us the amount of time it takes for combat rounds. Compound that with people being distracted while online, and I think 6 players will be a bit much. If you have everyone prep their turn, and streamline the enemies’ turns, it might be ok.