Spain could have eight teams playing European competitions next season. It will happen if Villarreal wins the Europa League (it would play the Champions League) and is not classified in the League in the positions that give the right to play in continental competitions.
Under normal conditions, LaLiga has seven European places corresponding to its UEFA coefficient. The first four will play the Champions League, the fifth classified and the Copa del Rey champion will access the Europa League and the sixth will go to the Conference League, the newly created European competition that will be released next year.
If Villarreal wins the Europa League and does not qualify for European positions, next season there will be 5 Spaniards in the Champions League, 2 in the Europa League and 1 in the Conference League.
If Villarreal win the Europa League and also qualify for European positions, Spain would lose one of the Europa League seats and would have 5 Champions, 1 Europa League and 1 Conference seats.
If Villarreal wins the Europa League and also ends up in the Conference League place, Spain would lose that place in the Conference and would have 5 in the Champions League and 2 in the Europa League.
According to which team wins the Copa del Rey today the distribution of European places will vary, Well, if the champion qualifies for European competitions (it would be the case of Barcelona), the sixth classified would go to the Europa League and the seventh would play the Conference League.
It could be the case that Spain had up to 9 teams playing in Europe next season. For this, in addition to the case of Villarreal, Real Madrid would have to win the Champions League and not to get into place in Europeans in the League, this second requirement being impossible this season.