Travelling to Bilbao from Geneva

Hi!

I will be travelling to Bilbao from Geneva in mid-August by plane. On the day I intend to travel, it seems that I only have options to fly first from Geneva to Barcelona and then to Bilbao. Both flights are operated by Vueling Airlines but their website shows that I still would have to do a self-transfer and check-in my luggage again in Barcelona

Is this really the case? If so, is there also a chance that I might have to go through passport control in Barcelona even if my flight originates in Geneva?

Any information is highly appreciated!