The OBP feature allows you to add for custom boards in SquareLine Studio. The board packages needs to be copied to the boards folder of SquareLine Studio. The added boards will be displayed on the Launcher screen in the Create menu.

SquareLine_Studio └── boards └── your_board_name └── version (v1_0_0) ├── your_board.png ├── your_board.zip └── your_board.slb

Read more at link below [https://docs.squareline.io/docs/obp]