It's not the same - that's buoyancy, not weightlessness. Gravity still exerts force on your body and internal organs, and you feel orientation, i.e. up and down. It's a very different feeling.
There’s no buoyancy without weight so it wouldn’t feel like anything until you moved. Then you’d have the same drag forces you would on Earth. It’s unlikely the sphere would stay together very long with nothing to hold it together.