Can I get BBC iPlayer in Spain?

Yes.
BBC iPlayer is designed for use UK residents only.
British expats living in US, Australia, Canada, Germany, UAE, or Spain cannot watch any content on BBC iPlayer directly, as their internet IP address will be blocked.

You can use a Smart DNS service, like SMARTDNSPROXY, to access BBC iPlyer in Spain.

For more information on Smart DNS services and VPNs for unblocking iPlayer in Spain > https://www.satandpcguy.com/on-demand-and-catch-up-tv-in-spain/smart-dns-services/