Fujifilm registered a new NP-W255 battery overseas for the upcoming/rumored X-T6 camera:
The new battery is rated at 2550mAh to support Fujifilm’s new X Processor 6 (the previous NP-W235 version was rated at 2,200 mAh).
Updated list of upcoming/rumored Fujifilm cameras and lenses
Via FujiAddict