how to obtain underlight angler after prepatch

[Mgemnusratsl]

I have underlight angler on 3 characters. I didnot have time for others before prepatch. now fishing skill is broken into expansions. do i have to level each expansion fishing to maximum or legion would be enough? it will be dull to go old content and fish up something you would never use(fishes). and since it is divided into expansions it doest not give you skill level for every fishing. in that case trying to obtain artifact won't be worthwhile.

[Acidbaron]

Believe you only need legion maxed