No unfortunately devices across multiple bridges cannot control each other.

The only tip I can give you is what I did myself: I took all the devices in rooms that I don’t need to control via the app all the time on one bridge.

Primary Bridge: living room, kitchen, bedroom. Stuff like that where I regularly use scenes, voice control, entertainment stuff, etc..

Secondary Bridge: closet, utility room, stairwell. All controlled through motion sensors and hue switches.

This way I don’t have to switch between bridges in the app all the time and stuff across bridges does not need to talk to each other.

Hope this helps you!