Because it is conceivable that there will be enough time to practice under Regulation Set G from when it begins on May 1st until the day of the Pokémon Championships 2023-24 Malaysia on June 30th, the Pokémon Championships 2023-24 Malaysia Video Game Division will use Regulation Set G.
Additionally, while it was written in the webpage for the Pokémon Championships 2023-24 Malaysia since the webpage was released and until April 24 that Regulation Set F will be used, that has now been amended.
https://rcs.portal-pokemon.com/2024/my/game/