Hi dwjung,
We currently don't have the map you requested in our map collection.
In general, a custom map could be created as described in general documentation here:
https://www.highcharts.com/docs/maps/create-custom-maps
It is possible to add shapes to create a new one. However, country boundaries will show. Border width or color could be set so the borders will not be visible in whole map.
Here's a PoC for adding shapes -
https://jsfiddle.net/BlackLabel/9pgtd57w/2/
Important options and changes:
-
https://api.highcharts.com/highmaps/series.map.allAreas needs to be set to false (or the underlying countries would have to be removed from the edited map to prevent overlapping)
- countries data for the parts of the merged region should be empty (commented out in the demo)
Only some countries from EU are added there, but you could use the code and extend the list of countries that should be added together. If anything in the code is unclear please let me know and I will add info about it.