Surface Edit > Reverse Surface UV

Reverses the parametric direction of a surface (U or V), or swaps the U and V parameters of a surface.

Reversing the U or V parameterization, or swapping the U and V parameters for a surface does not affect the direction of the normal.

Reverse Surface UV Options

Display direction(s): All intersecting – Display the U and/or V direction of all surfaces under the cursor.

Closest to eye – Display the U and/or V direction of the nearest surface under the cursor.
Surface Reversal Mode: Reverse U direction – Reverse the direction of the U isoparametric curves.

Reverse V direction – Reverse the direction of the V isoparametric curves.

Swap U and V direction – Swap the isoparametric curves so that the U direction becomes the V direction and vice versa.