Looking at the history of the games (not the anime) this is how i see it.
Battle network and the original megaman series (which has progressed to the point of the X and zero years) seem to play out the same in terms of concepts. I.E megaman and roll both fight together, protoman is rogue and is also sort of rogue IN THE GAME of battle network. Bass in both timelines is constantly after megaman (although he seems to forget every time you meet him in game). Iris and Colonel are still brother and sister and in BN 6 a lot of original ideas were incorporated into the explanation of how they were created and related. Even zero was included in the battle network series but was extremly underpowered and appeared in Network Transmission for the Gamecube (quite unpopular) as a virus. Dr.light (if my memory serves me well) is represented as grandpa Hikari who worked along side Wily (who in the battle network series is perfectly equivalent to the one in the original series) and who's inventions also correspond with that of the original series e.g. the light program and Megaman himself. The idea of souls really comes from the idea that in the original series upon beating a boss you got one of their skills and when you had them equipped your colour would change.
so no doubt they would do the same when making starforce in order to keep a sence of legacy? the ideas that this is true in the case of battlenetwork to star force is as followed:
Lan's net navi was megaman - Geo resembles Lan in physical appearance and can wave change with omega-xis to become megaman.
in battle network Megaman fought along side roll (aswell as Gutsman etc...) who's operator was Mayl - Harpnote happens to be the only other "good" FM-ian that fights along side Megaman and is arguably the roll of megaman starforce and in human form is Sonia who also arguably resembles Mayl (more so in terms of personality aswell).
One of Lan's friends was Yai the spoilt rich girl who skipped a couple years because she was so clever, nothing of importance to do with the actual story line - Luna is the same concept, rich, spoilt, smart (yet blonde
) but of course has her own unique qualities (but that can be said for Sonia aswell)
Lan married Mayl at the end of BN 6 in a scene that was meant to be the future - [future input required from starforce series]
if you see the pattern ive pointed you will know whats going to be put in those brackets. To those who say in game Geo does also fight for Luna i say Lan always fought for his friends aswell so? To those who say this is just a theory you cant prove anything i say yes it is just a theory but considering it is theres a hell of alot of proof supporting my view
and then again thats really all we have to work on, theorys and opinions.