Hey there,
For the most part it’s fine to post one game to multiple game jams. However keep in mind that if a game is submitted to multiple game jams and it doesn’t fit the theme, it might be seen as spammy behaviour, and you might be prevented from posting on any more game jams.
It’s hard to tell where the line is drawn, but in general, if there’s a couple game jams and your project fits on all of their themes, then it should be fine.
Hope that helps :)