PSA has not always maintained the same grading standards
There can be small tolerances for trimming and cutting in large production runs, or millimeters may round a bit
Because these cards arent at an especially high power level I expect the regular Magic Online offerings to eschew the mechanic entirely, and if you do want to incorporate dungeons into one of your Cubes I recommend going heavy on the mechanic so that players have good odds of actually completing one
This is especially good when some players are Final Fantasy fans first and Magic players second, because the card names and worlds create instant interest
I would try and get this line out in the active Pokemon spot early and use Psypunch most turns, and while you're waiting to get three energy cards on Metang, definitely use Psy Bolt so you can spend some time setting up your benched Pokemon while your opponent cannot attack
For reference I use normal Ultra Pro sleeves, nothing fancy