Many digital effects will likely need to be created for whatever mystical MacGuffin is at the core of the movie, as well as lots of green screen work to create sets for any filming not done on location.
The current release date for Indiana Jones 5 is July 9, 2021.
One assumes a movie like this is going to have significant post-production work that needs to be done.
That may seem like a long way off, but it’s really not.