godot has alternate tile sets. an alternate tile is a modified version of an original tile.
below is a note from the documentation:
Godot 4.0 has moved several per-tile properties, such as tile rotation, from TileMap to TileSet. Individual tiles can no longer be rotated while in the TileMap editor. Instead, the TileSet editor must be used to create alternative rotated tiles. This change allows for greater design consistency, as not every tile needs to be rotated or flipped within a TileSet.