Yes it's in your settings, the Export/Import JSON file, easier done with a desktop - in case you ever need to give it a try! :-)
My problem is that I tend to keep up multiple accounts at a time, bc random server issues creep up (like Kbin.Social that I had to abandon; and then StarTrek got extremely slow and 75% of the time I try to make a comment it would fail). So probably I should make use of this feature more to keep the blocklists more updated:-).