Well, while trying to scout trainers, I dump their Pokémon in order to see if they've brought good sets in their 1st and 2nd slots, so I've seen plenty of them. Though lately I've been overwriting a single file in order to keep my desktop clean, the first times I did it I made each dumped Mon an individual file. Since I keep my recycle bin with whatever I've sent there just in case I'm gonna need it someday, they were still in there. Here they are:
350 - Milotic - 3811F0878FB1.pk7 - Leftovers set, dumped from Cynthia.
442 - Spiritomb - F822650BD255.pk7 - Custap Berry set, dumped from Cynthia
445 - Garchomp - 249534DF029B.pk7 - Scarf set, dumped from Cynthia, and (at least) used by Wally as well
448 - Lucario - A90C7D3885D8.pk7 - Weakness Policy set, dumped from Cynthia, and (at least) used by Anabel as well
625 - Bisharp - 6A8FACD770AA.pk7 - Chople Berry set, dumped from Guzma, and (at least) used by Grimsley as well
748 - Toxapex - C6285EB975B5.pk7 - Red Card set, dumped from Plumeria
754 - Lurantis - BBB38BA0484B.pk7 - Wrong item (Smooth Rock instead of Heat Rock) set, dumped from Breeder Kiernan
768 - Golisopod - 783327169442.pk7 - Quick Claw set, dumped from Guzma
776 - Turtonator - CED4192D8279.pk7 - Wrong item (Smooth Rock instead of Heat Rock) set, dumped from Breeder Nedry
784 - Kommo-o - B56873E8D010.pk7 - Pre-patch Shell Smash set (Illegal), dumped from Preschooler Naya, and (at least) used by Preschooler Victor, and Madames Donny and Gracie as well.
It should be noted that:
These Pokémon have preset natures, IVs, EVs, movesets and items, but their genders, abilities and PIDs are generated at the moment you encounter them. In other words, if you find one of the sets I uploaded elsewhere and that data differs, they should still be valid Battle Tree sets.
Whereas some trainers share the exact same sets for some Pokémon, their Balls may differ due to their classes.
Some of these Mons will have "Sun." as their OT because they were dumped from recorded battles, but some others shouldn't have an OT at all due to being dumped directly from the actual battle. That's not an error.