April 1 there was a FOIA document dump at the State Dept. It has some internal documents and emails about the Iran payoff of $400 million in cash for hostages (made some people pretty mad internally) and how they had to deal with the press.
I get the impression that the whole payoff was coordinated through the White House and a lot of the folks at State were left out of the loop.
There is older stuff, even some emails about Iran between Hillary and Sid Blumenthal that were exchanged on her private server.
https://foia.state.gov/Search/results.aspx?searchText=Iran