Basically, no matter what your opponents choose to do, Rhystic Study will be super annoying for them to play around, and whats annoying for your opponents is great for you
Since "Swordsoul Tokens" are always Special Summoned with an effect that also prevents the Summoning player from Special Summoning any monsters from the Extra Deck (except Synchro Monsters) while the Token is on the field, cards such as "Dimensional Barrier" (declaring "Synchro") or "Discord" will prevent them from Summoning Synchro Monsters too
This will keep Barbaracle armed against effects like Klefkis Memory Lock
Flooding your opponents hand with land cards beats the hell out of just drawing them cards, and youll always get to see what nonland theyre about to draw
Note that most of the time, this is irrelevant - you're going to use them for Extra Deck plays anyway
This attack also does 40 damage to 1 of your Benched Pokmon