Everton’s impending takeover by AS Roma owner Dan Friedkin faces one serious hurdle. The US billionaire, who is believed to be worth around £5bn, has struck an exclusivity agreement with Farhad Moshiri. Both parties have now entered into talks to define the exact terms of the sale of Moshiri’s 94 per cent stake in the club. Friedkin was one of around nine serious candidates to purchase the club. Among them were MSP Sports Capital and MSD Partners, who are part financed by Michael Dell. Those groups, like failed takeover suitors 777 Partners, are all linked to multi-club models. And that struct…