Oh this is so cool! Welcome! @prog and @louis, both also based in Geneva, have respectively experience with Wikidata and with setting up our own instance of Wikibase.
Are you going to WikidataCon or Wikimania?
The community will need lots of help, I suspect, for instance here.
I have made lots of choices around setting up our own Wikibase, which I hope to be the right ones or at least can be revisited.
What I don’t know is how to interface data between the two, to make the interaction as mutually beneficial as possible. I suspect the best way is to pick a country, say Switzerland, and try to import all the companies from that country to our Wikibase – along with a few relevant attributes – while keeping track of identifiers from Wikidata. What do you think of this plan?