Where do you get Type: Null in Sword/Shield?

Question

I want to have a Type: Null in my party just in case you asked.

Answer 1

here-
Type: Null can’t be encountered in the wild. As with previous games, Type: Null is only given to the player from an NPC. After beating the game, you’ll gain access to the Battle Tower located in Wyndon. Inside the Battle Tower, on the left side of the lobby, there’s a character standing next to a Type: Null. Speak to this character and they’ll give you your own Type: Null.
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Answer 2

Head to Wyndon, and take the monorail to the Battle Tower. In the lobby there, talk to the lady with Type: Null next to her, and she will gift you Type: Null and it's Drives.

Source: Experience