2 official rulings from Bandai, last ruled Mar 28, 2024. Straight answers to how this card actually resolves.

Is this card’s play cost reduced by 1 for each Option card in ONLY my trash or my opponent’s trash?
No, its play cost is reduced by the total number of Option cards in both you and your opponent's trashes.
Ruled Mar 28, 2024
I use this card’s <On Play> effect to return cards from both players’ trashes to the bottom of their owners’ decks. Who decides which order the cards are placed in?
The player who activated the effect decides the order in which their cards and their opponent's cards are returned to the bottom of each player's decks.
Ruled Mar 28, 2024
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