For anyone who wants to know where the Switch Palaces are in Mario X World: Bowser's Strike Back, cuz they're stupidly hard to find outside of opening it up in Lunar Magic:
ムジナさばくの こだいいせき (Mujina Desert's Ancient Ruins) - World 3 Ghost House:
The quicksand pit in screen 0D (the one right before the fourth Dragon Coin) leads you to a hidden room rather than kill you. This will lead to the Green Switch.
ヒメハギシティの こうじょう１ (Milkwort City Factory 1) - World 4 Factory 1:
Pipe in screen 0B (second pipe after the third Dragon Coin), leads to a hidden room with the key and keyhole. You need the cape, which can be obtained from earlier in the level, to open the block with the key as it's on the ground. This will lead to the Red Switch.
カトレアジャングルの しろ (Cattleya Jungle Castle) - World 5 Castle:
In the vertical section after the midpoint, at the highest end of the first line lift, jump towards the upper part of the right wall.
This will lead to the Blue Switch.
エゾマツだいちの れいはいどう (Yezo Plateau Chapel) - World 6 Chapel:
Third to last stairs before the end, run towards the wall behind them as small Mario.
This will lead to the Yellow Switch.