If we don't sign a CM this season, that means Pogba is staying. Having him, Bruno and the expected ball playing improvement from CBs might be enough for creativity from the middle with Cavani being good with heading the ball from wings. It makes sense to buff the wing attacking play this season for that. Frankly, it was a tad shit last season with Rashford not playing well and the right side being the right side despite AWB improving a lot.
The middle along with a striker will probably be addressed next season with both Pogba and Cavani likely to go out.