One method involves using the Wishing Star item. The Wishing Star can be found in different locations throughout the game, and when used, it grants the user one wish. One of the possible wishes that the Wishing Star can grant is to duplicate a defeated Pokémon. If the player uses the Wishing Star to duplicate Virision, they will obtain a copy of Virision that they can use in battle and train like any other Pokémon.
Another method of obtaining Virision's power is through the use of a Memory Bottle. The Memory Bottle is an item that can be obtained by completing certain quests in the game. When used on a defeated Pokémon, the Memory Bottle captures the Pokémon's memories and techniques. If the player uses the Memory Bottle on a defeated Virision, they will obtain a set of moves and abilities that can be used by other Pokémon.
These methods allow players to obtain and use Virision's power without having to capture it in the traditional sense.