Real Madrid
Los Blancos are struggling badly at the moment, in both La Liga and the Champions League.
Their most recent loss was to Levante, and it's possible that Lopetegui may face the sack soon. Their next game is against their old "friends" in Barcelona, the El Clasico, and a defeat to them may mean the end for their present manager.
If this happens, then who knows, it could mean Wenger unites with a club who strongly wanted him around the mid-2000s.
Whilst Wenger is not known for his defensive strengths, the players may welcome the focus on attacking qualities, and given the successes that they've experienced, they may hold the mental and psychological strength to be intelligent footballers as Wenger demands. This is a major reason for the success he enjoyed in his early Arsenal tenure.
Wenger is used to high-pressure environments and is fluent in Spanish, so he could fit in readily if required.