In order to get into the split decision ruins do I need to catch the regis or open the doors?

Question

If I trade the regis in via Pokemon Home.

Answer 1

Just tested it you need to catch all the of the regis from the chambers.

Comments

That was a fast best answer

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I was in the middle of testing.

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Hmm... Interesting.  Want me to hide my answer?

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Yeah it's wrong

Answer 2

To enter, the player must have Regirock, Regice, and Registeel in their party after advancing to a certain point in Crown Tundra's story.

Source: https://m.bulbapedia.bulbagarden.net/wiki/Split-Decision_Ruins

Since you just need to have them in your party, you can trade them from Home and it should work.

Edit: Turns out you need to catch them from the chambers.