UE5 engine keeps making R8G8B8A8 textures to grayscale textures.

hi,

we’re using UE 5.2

UE5 keeps making color textures without color to gray textures.

reproduce method :
-make textures in photoshop (RGB/8)
-use only grayscale color
-no alpha
-export to UE5

UE5 forces to change B8G8R8A8 to G8 even texture is made of RGB/8
if i use as B8G8R8A8 texture, i had to add some alpha area or paint some colors on purpose then it works as B8G8R8A8.

the problem is using as sprites, atlas.
-can’t see sprites.
-atlas can’t support G8 textures.

we’re using Sprite Atlas Group Plugin

is there any flag or method to disable removing texture’s channels?