Oh yes, it can be.
The color will change automatically to match the palette. Hopefully you were going for that, but if not you can just un-index the image and then paste the tile in there. Or if you saved a version of the image un-indexed already.
Here, I'll even post a picture doing so.
Gale's .PAL files it saves seem to be bugged and I didn't realize it until just now.
When you load a palette file that you saved in gale the colors end up darkened.
I will continue seeing if there's a way to fix this, but for now I would like to recommend; do NOT using Gale for palette saving. Only editing.