The laser plane would have to take out all the fighter planes first.
Not a problem.
For fighters the range is shorter and the speeds are lower and the vulnerability is greater.
Missiles headed into the laser carrying plane would be the toughest target , but these can be burned also.
I expect it would work best to have two or more laser carrying planes so that they could cover each other somewhat. Missiles are much more vulnerable to laser burn on their sides than on their noses.