I've talked this over with some others to get a wider perspective.
I'd be comfortable uploading or linking to it as a free fan translation, French speaking players would have free access to the game. If they like it and want to support me, they can buy the English version.
As soon as I put it behind a paywall, from my perspective I'd be obligated to pay you and provide customer support for the French version of the game.
I'm incredibly grateful that you like my game enough to have translated it and to offer this. It's important to me to handle this carefully, hence my responses.