Not sure whether you are looking for the pinching look like you sketched on the left side or if the texture would needd to be just oriented along an axis…
Yes I saw it but I don’t understand how you did it !
I try different functionality but it is always hazardous.
So you create a surface with the same shape then custom mapped your original surface by selecting the new surface.
It gave me this really difficult shape to mapp
I try to change the degree but give me only bad result