The naval drone question is especially fascinating.
IMHO, they have to be transported closer to impact site by some other vessel.
Ukraine doesn't have submarines, and Russia has 6(?) Kilo's in the Black Sea, so traditional submarines would be insane in that environment anyway.
And whatever transport method would need to be stealthy with respect to Russia's sensing methods: acoustic, radar, to a lesser degree visual.
Given Ukraine's technical capabilities and traditional shipbuilding expertise, I'd hazard there's a somewhat-stealthy drone carrier boat (probably also unmanned).
They could also be hiding/launching the drones directly from commercial shipping, but that's an awfully big risk for the flag country/ship owner with respect to Russia boarding and searching, or even back tracing launch points.