Tile a bit proud because of tile edging
One approach is to build up more tile mortar/mastic on the second row. Trowel it onto the wall, and also back-butter the tile, but in the perpendicular direction. This gives you more &quot;squish&quot; to work with so you can match the level of the first row.
You could also have rabbeted the edging into the backer board, but that's kind of a messy job.