Would a 12v battery be workable? I posted in the lounge about this 12v RF remote I found to use for camping lights and fans. Main thing is, I can control it from Hubitat with a Broadlink RM Pro by using the RF signals captured from the remote. There are lots of 12v lights out there you could use, and this can dim them if they are dimmable.
There are also these devices that would let you control non-smart 5v lights run from a powerbank.
