A python script that generates Anki decks for Interslavic language in different languages. Data is sourced from https://interslavic-dictionary.com/
The Anki decks are available at https://ankiweb.net/shared/decks?search=interslavic
Pick the comprehension deck if you want to prioritise learning reading
Pick the production deck if you want to prioritise learning writing
As for the language, use whichever language is your strongest.
The comprehension deck is multi-lingual, you can change the order of displayed languages in CSS options in Anki.