The Hex spell reads
You place a curse on a creature that you can see within range. … If the target drops to 0 hit points before this spell ends, you can use a bonus action on a subsequent turn of yours to curse a new creature.
Hex still requires range and sight requirements to be satisfied when re-applying because of the first line of its description but I am uncertain whether the Targeting limitations apply when the spell is not being cast?
The precise situation I am thinking of is moving Hex to a target that is visible through a transparent window. I suspect the answer is no but would appreciate a deeper understanding. A related component of this question is whether moving Hex is considered to be moving the effect or having multiple targets.
Does reapplying Hex have any spell components?
Changing Hex to Unseen Targets out of Range