Regional Long Haul
Is an airport manager's wet dream. They are always in "talks". However given that it is extraordainarily tricky to have succesful long haul with an established competitor next door, I doubt any established carrier could make Liverpool a success.
Stansted doesn't work as the critical mass is at Heathrow. Gatwick has carved a niche in leisure long haul that matches it's traditional demographics whereas Bristol just lost Continental as too many were using the Heathrow option due to more times, connections and for some a bigger aeroplane.
Given that MAN is only now re-establsihing lapsed long haul schedules, what does Liverpool bring to the table that won't be undermined by an existing MAN service. It's not like AMS, long haul is a different beast.
BTW These figures have a load of double counting as loads visit London and then do somewhere else. This does not mean they will want to fly directly to Liverpool or Glasgow as loads still arrive intending to do London and Edinburgh and A.N. Other.