Can you check with the city of Barcelona* if they would like to host such an event? Maybe we can prepare some proposal to forward them? As I see it, it would not happen before Spring 2020 (since things usually get some time to organize, it’s easier to plan well in advance, and Spring in Barcelona sounds pretty nice).
If BCN is up for it, that means people can tell their bosses to sponsor their flights, and so on. Thoughts?
* Or maybe Hangar, or a local hacklab… But I would try Francesca Bria first