Dynamaxing seems to be exempt from a lot of things. What about Sheer Force?
Some of the Nerds wonderful people of Smogon did a bunch of tests in game and concluded a lot of things, such as:
Sheer Force does not power up the moves or remove the effects (SadisticMystic)
Contextually being applied to max moves
Source
Hope I helped! :P
Sheer force does not eliminate the effects of the "max" moves achieved after dynamaxing.