Re: Reactions Sam will probably do another speechy post, not right after Steve's, but when the news has had time to settle in just reassuring people and probably giving them distractions or something. He has fairly mixed feelings about this whole thing.
Laura immediately goes to spend time with Morgan, especially since Pepper's busy handling the fallout. She'll probably be with her much of the weekend unless Morgan wants alone time.
Storm has just posted offering help to Pepper since she's run stuff even more complicated than this place.
Melissa will probably go turn up at the Lighthouse to see what SHIELD's doing
Elsa is ¯\_(ツ)_/¯
Cassie is very concerned but doesn't really have much to contribute here so is just sort of floating around restlessly
Roman is in quite a grim mood and will be systematically exploring the facility to make sure nothing escaped from the portal that no one else (excepting Klaus) could see. Hurray, no ghosts. That doesn't make him feel much better though.