I've created tons of textures for oblivion mods, and while I probably haven't made as many as is on the characters of ffx , It doesn't take very long to make textures. I had no idea about handpainted though, all mine were done in photoshop, then mounted using other programs

I was under the impression that this was going to be along the lines of jak and daxter hd, with just the character textures really increased and the rest just smoothed or sharpened with new colors.
If they are doing a full hd remake and adding new meshes, yes it will take a long time, because meshes are a pain in the ass to create, but if it is just updated textures, the actual art part shouldn't take too long.

Unless they are actually hand painting them, I would like to see where you came up with that.