It's a tricky question indeed!
...Alien 5 is heading to a not-so-popular part of the continuity, probably after Resurrection.
...The Covenant sequel is heading toward a not-so-popular but interesting part of the continuity.
Note ~ Although the fact that they are using elements from the prequels in the new EU seems to suggest that not everything is lost in this territory. The question is whether a final prequel from Ridley Scott is still possible.
...A movie that is directly connected to the next TV series sounds likely. Although we are still not clear in which part of the continuity takes place.