Hi MaryAnn,
This is a great question. With it’s gentle yet powerful support to clearing lungs, one could assume that it might be a good ally in grief work and I would say that this could be the case. I haven’t read this specifically but there is folklore around hyssop for purification and cleansing, which could be a direction in the way it could support the grief process. Depending on where a person is in their process, hyssop may or may not be the best plant for that time.
I think (as will all plants) the best thing is to work with the plant and see how it feels, this is one of the best ways to learn and embody the shared wisdom of each plant.
I hope this helps give you some direction.
Warmly,
Benna