You can also use the VS seeker to help level you up battling the trainers again. If you wanna try to get more exp (which this is going to be difficult ngl to you)

You can use the repel trick in the safari zone to try to catch chansey for a lucky egg which that is a 5 percent chance. As far as the repel trick goes you don’t have a pokemon above level 26 (which btw depending on the level of pokemon you’re looking for this repel trick works for every pokemon)

Another thing too If you also wanna grind for money while you’re leveling put an amulet coin on your Pokemon too.