Haven't tried the widget but the problem is that the local dimming setting isn't saved as part of the profile and I would assume the same goes for when using the software. Can you even change all settings via the software that is available in the OSD?Can't you use "Acer Display Widget" software to switch between the "work profile" and the "entertainment" one?
Acer Display Widget let you export/import settings rapidly. I use it to switch between the calibrated profile and HDR on my XV273K.
But regardless, these kind of problems shouldn't even be there on a monitor this expensive. Having to disable local dimming just to get acceptable brightness just isn't in itself acceptable.