How would it be possible to use oblique projection with Tiled? My issue is that I would need a lot of layers for it to work, otherwise it just replaces previous part of the wall.
It seems you have already found out the “perspective_walls.png” example tileset. If you open the “perspective_walls.tmx” example map, you’ll notice that while the map as a 32x32 pixel grid, the tileset “perspective_walls.tsx” actually has 64x64 tiles. This way, the tiles will extend beyond their grid cells, allowing for this type of oblique projection to be achieved.
Additional layers are in principle only needed when multiple tiles should sit in the same location, for example when using separate terrain tiles or when stacking tiles (as also done in the example).
Btw, I see that your tiles (at least your trees) are extending to the top-right, instead of to the top-left as in the example tileset. For those tiles to overlap their neighbors correctly you’ll need to change the tile rendering order of the map to “Left Down” in the Map Properties.