Spain has implemented ERC/DEC/(98)25, 26 and 27 legalising use and free import from other EU states of PMR446 radio equipment; the 8-channel radios you describe. So, the answer to your question is yes!
PMR 446 was introduced as a pan-European service a couple of years after we in the UK introduced Short Range Business Radio. So yes there is no problem using it in Europe.
HOWEVER, to anyone reading, Don't confuse the US version "Family Radio Service" with PMR 446, although a similar service, it is only legal in the US. The frequencies involved are completely different from those in Europe and its use in many European administrations will land you a "no way out" instant fine.
Second that. Be especially careful of buying such radios from eBay where American FRS radios are commonly advertised and look identical to PMR446 versions. The obvious give away is that they are 14-channel and not 8.