Splitting large multipolygons

[anonymous]

I have tasked myself with splitting [
​https://www.openstreetmap.org/relation/1560792 this beast] into many multipolygons. The main reason is lower complexity and fewer members.

Is it possible to do this easily in JOSM?

I see that there is a plugin named RelationDisolve but no plugin for splitting relations.
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Wish list:

• Best: ability to automatically split into x relations (JOSM determines where to split them and generates the ways needed without crossing any inners)
• Second best: Ability to split along selected way(s) and delete inners from the former relation and add them to the newly created relation.