Well I kinda think that Fenris will be a bi LI of DA II and I will try to ellaborate on that:
Sebastian: He is DLC content so he is an "optional" character for the story, so if he is LI will be for both sexes but he wont be the only bi LI since you will have to buy the DLC in order to get him in your party
Varric: As we know he is the narrator, and if I was Cassandra I wouldnt go to the lover of the champion to get any info for obvious reasons.So i kinda think that Varric wont be an LI
Anders: Anders was a member of your party in DAO, his official descreption back then stated that he enjoys the company of women furthermore if you had a female warden he was really flirty, that didnt happen with male wardens. We know that in DAII he is a "roommate-lol" with a spirit so he is changed however i highly doubt that a spirit would alter a persons sexuality, usually spirits prefer to mangle with other aspects of a person's character ,there are exeptions ofc-lets say the Lust Deamon, but i think that justice/vengeance wont go there
Fenris: His story arc is really interesting, we do know that he was raised as a living weapon that he bears an aversion for human touch and that his master still hunts him, these elements make his story interesting but I think the possibility of romance makes the whole thing much more intriquing and dynamic so if the devs decided to make him LI it would be for both male/female Hawkes in order to give the opportunity to experience his story arc in a proper way for both sexes
So I bet that the LIs will be the following
Anders : female LI
Fenris: bi LI
Varric: not an LI
Seb: Either for both or for none