At a event in Los Angeles ( black panther event), Kevin Feige spoke to entertainment journalist Erick Weber and shared some details, Here they are summarised-
1)AVENGERS 4 Trailer definitely before end of the year(ofc)
2)Namor Could make an appearance but they are still deciding when and where
3)Guardians 3 is ON HOLD :(
4)Marvel is moving forward with Eternals, Black Widow and those shows of Loki and Scarlet Witch