Is it ok to write on the hotcoat with a pencil then gloss over it?
yeah, it shouldn’t be a problem.
Pencil could smudge a little. Have you tried India ink? Get it at an art store with some quill style pens. Pencil has a kind of shabby look. The ink looks sharp. Don’t want to change your “vision” if your heart is set on it. I’ve done some really intricate work with India ink; tiny writing and super detail. You can easily scrape away mistakes with a razor blade. What the heck just an option… Have fun.