I can’t speak for the HABApp parts but in general you have to watch out for infinite loops. You never want to subscribe to both commands and events at the same time or you end up going around and around as a command results in an update which ends up in a command and so on. I discuss this quite a bit at Marketplace MQTT Event Bus which is pretty much exactly what you are proposing except with a HABApp implementation instead of using the built in OH Rules.
Generally, one instance of OH will “own” the device. The device owner will only subscribe for commands and only publish updates. The “remote” devices will only subscribe for updates and only publish commands. Ideally you’ll also want to turn off autoupdate on the “remote” Items so they don’t change state until after the “owner” OH reports that the Item changed state.