Depending on your sprite resolution, a possible fix may be to first find the camera zoom that makes the art look good when zoomed out max. Then every zoom-in is an integer multiple of that (like 2x, 3x, 4x). You could still lerp/tween between 1x and 2x for example, so there will be aliasing as the camera is moving, but once it reaches its destination it should snap the pixels correctly
--- though looking at the art again, I don't think this solution is possible unfortunately