Until this moment the GUI import function is still missing, I'd love to have such an useful feature.
IMHO one of the problems was the unique IDs of the entities which could be "somehow" conflicted between the source & the target systems (i.e if "by one in a billions chances" there is an existing IDs, it would update this existing entities instead of creating a new one).
However, when I tried to modify the JSON and manually created new IDs (any how you like, there is no restriction that I encountered yet), I can insert the entities (such as variables, projects, ...) via direct SQL queries. So far the system is still working fine. I wonder if that could be a proper workaround.

That would be really useful.

I am soon on boarding octopus with hundreds of projects with different app teams. alot of the variables are the same and dynamic. Please add this to save time.

this would be useful when migrating between on-prem and cloud (or visa-versa).

The migrations team @ octopus are only doing 1 migration a month and none at all at the moment!

I can't see the point of the export if there's no corresponding import?

I have 20 projects to migrate, some have hundreds of variables (including test/uat/prod variations)... it's a long and laborious job !

I too would love to see this feature within octopus.

You can currently export project variables to a JSON file. However, there's not a way to import this JSON file onto another Octopus server.