Gate Soldiers are NPCs in BLACKSOULS 2 you can find at the Garden of the Heart after going through the fog in a hallway left to the Ripon Grand Cathedral at the Liddell Cemetery. These guards are protecting the entrance to the Garden of the Heart area, and you have to get through them first if you want to pass.
The Gate Soldiers are called Knapp and Oreon. They can be hard to beat, specifically if you’re at the beginning of the game.
You can fight these guards, but you can also get through them by showing them the Gate Pass you can get from Bill if you go through his dialogue.
This pass is a love letter, which is quite cute and funny. If you tell these guards you got the pass from the Bill, they will let you pass through.