In Galar, Linoone has a dual-type Dark/Normal regional form. It evolves from Galarian Zigzagoon starting at level 20 and evolves into Obstagoon when leveled up at night starting at level 35.

How do you evolve Linoone into Obstagoon?

Galarian Linoone turns into Obstagoon if it is reaches level 35 or higher at night. No matter what time the Nintendo Switch's internal clock says it is, Pokemon Sword and Shield only count a Pokemon as evolving "at night" if it's actually night in the area a player is in-game.

Why is my Linoone not evolving?

Linoone will only evolve at night. ... Once it's night time in game, your Linoone will need to be level 35 or higher in order to evolve. If it's close, you may only need a couple battles or rare candies to get it to that point. Otherwise, level it first and then mess with the time of day.