Exporting json that has a structure constructed from elements matched in DB

I have a graph structure that looks like the one on the left and I need a json file with the structure to the right

the purpose is to get a list of counties with , for each of them, the corresponding list of collectives names, with optional attached details (url by type - facebook, twitter or website and email address)

here is for example how county n°13 looks like in DB : it has 3 collectives attached. Urls are the green nodes , an email address is node with property thgType="email adress"

do I need to create , in the DB, the nodes and relations corresponding to the structure I want to export ?

if so, how do I do that ? i've been struggling with foreach, unwind, create, call , ... and could figure it out !

do I need apoc.convert.toJson ? cause I got this error trying to use id

Failed to invoke function `apoc.convert.toJson`: Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: No serializer found for class org.neo4j.graphdb.Label$1 and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: java.util.ArrayList[0]->org.neo4j.kernel.impl.core.NodeEntity["labels"]->java.util.ArrayList[0])

any hint on how to construct a new structure by picking elements in DB highly appreciated !

(tried my best to make the question clear, but please ask if it is not ... )