Guild Wars 2

does condition duration (from runes especially) apply to transferred ones? so if my necro had +15% burn duration and i threw a dragons breath back to an ele it would be longer?

It only applies to conditions that are cast by the player.
Transfering already existing ones merely copies their remaining duration.

Just wondering, is that the same for copied ones via epidemic too? Or are they all set durations like when you corrupt boon? Thanks.

Epidemic follows the transfering principle, it copies the durations as well.
Corrupt Boon creates new conditions on a target, therefore the casters condition duration applies.