Roxie said that Solgaleo was giving off an even more intense vibe while absorbing sunshine in the first scan. That's the game explaination for Solgaleo's stat difference between 2 stages. It's also my bad for not add scans of the two battles of pre-energy absorption stage and post-energy absorption stage. In the first stage, Roxie, Hau and the Protagonist were able to defeate Solgaleo and his team. But in the second stage, the result was inconclusive.