In Guardians of the Galaxy 2 . . .
Ego reveals he planted pieces of him throughout the galaxy, including in Missouri on Earth. With Peter's help, he begins to activate them and these pieces of him start growing in giant blue blobs that consume everything. The exact timing of GotG2 isn't entirely clear, but given this was a serious (and extraterrestrial) event that occurred on American soil, I'm sure it would have gotten the attention of S.H.I.E.L.D., researchers like Erik Selvig or even the Avengers.
So given that, are there any references to it other MCU titles such as Agents of S.H.I.E.L.D. or a tie-in comic?