Depends whether or not it's enough to stop Cell's transformation, since we know his full power perfect form was enough to trounce Trunks. If Cell is still able to transform in time, he'd quickly regenerate any damage done and trounce both Vegeta and Trunks, though events ultimately play out the same from thereon. Maybe being more aware of Cell's true power here would cause Vegeta and Trunks to train hard enough they can beat the Cell Juniors they face, but that's about it as far as changes go.
If Trunks destroys Cell by doing so, then it seems doubtful Goku or Vegeta would achieve SS2. Goku and Vegeta would also likely fight as they seemed to have arranged for after Cell was beaten, with Goku trouncing him further fuelling Vegeta's rivalry. To avoid a whole "what form was Gohan using?" debate, I'll just say Dabura's more comparable to his future self due to timeline changes (if it leads to #17 and #18 being stronger in the main timeline for no reason, I don't see why not
). That said, Goku's immediate plan of action is to take Gohan into the Rosat, both of them managing to unlock SS2 by the end. Whether Gohan fights alone or they take him on together as a precaution, Dabura is defeated, with Vegeta letting Babidi control him due to the difference that has formed, likely unlocking SS2 through this method. The Rosat would be enough for Goku to have the edge regardless though and Boo isn't revived.
Super goes relatively the same beyond less stakes in the BoG Arc due to Beerus eventually asking about SSG rather than Boo making him angry. Changes really start occurring either in the ToP at the earliest or Moro Arc at the latest. Gohan not having Rou-Dai Kaioshin unlock his potential may cause him to be far weaker at the start of the ToP and possibly eliminated far earlier. If so, the stamina taken in U7's fighters beating Kefla (if they even can) leads to Jiren winning. If not, the Dragon Team would still be fucked in the Moro Arc as the lack of Boo to fully heal them means Goku and Vegeta are killed by Moro on New Namek, or if surviving by some miracle, they die to Planet Moro due to Oob not being able to transmit God Ki to Galu.
