No it has to be fully heated, otherwise the nozzle length would be quite different. However the oozing is annoying I agree.
The balls of filament is caused by the nozzle sliding over extruded filaments. I’m not sure of why it’s happening on H2D, but I would blame it on Bambu for not coating their nozzles. I get exactly the same blobs even on my X1C, but then I solved it with the Phaetus Conch Plus hotends as they come with anti-sticking coating. It was a beautiful hotend and sadly we have to wait until it arrives on H2D