Implications for Villarreal if Sevilla win? None as far as where we start the Europa League next season; UEFA has said if Sevilla wins, their spot in the EL group stage will be vacated, but teams from the same association won't get it--instead, the cup winners from various associations will see their entry points adjusted to fill it.
If Athletic Club win the Copa del Rey, they get a group stage spot, Villarreal go through the playoff stages. If Barca win, Villarreal get to start in the group stage.
However, there is still good news for Villarreal in case of a Sevilla win--since there would only be two Spanish clubs in the EL, us and Athletic Bilbao, the TV pool money would only be allocated two ways instead of three. In case of a deep run in the EL, this might add some decent sum to the payout.
I'm going to be supporting Sevilla today because they deserve CL football--never before has a team in Spain gotten so many points but not qualified for it directly. If anyone is watching and wants to post comments as the game progresses, please do so.