Sorry, 2D physics effectors aren't supported yet. I've logged an Idea to keep it in mind for a future version. Merging both topics.
Awesome! Keep up the amazing work!! ^_^
Upon further testing, the BuoyancyEffector2Ds damping and flow parameters do seem to still be functioning. So it's just gravity not getting partially canceled out based on the effector's density versus the body's.
Will update if I'm able to implement a solution~
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