can you flip normals of a static mesh or character mesh

Im trying to make an outline shader that doesnt rely on the post procress method. I like to make the classic shell style one. I know how to make the shader push the verts out to create thickness but i cant seem to figure out how to flip the normals of the poly’s

draw 2 sided would suggest or imply that is possible.

im also aware that i d have to create the mesh twice in game, but if there was a way to do it all in one shader that would be great.

when searching flipping normals all i can find is people importing incorrectly

I dont think thats possible, I havent come across that kind of thing at least.

Hi. I know how to invert faces and I know how to make push effect, but I don`t know how to add this effect to invert faces block.

hehe blast from the past post. Curious to hear what the technique is if its something i havent considered yet