今回はThe rockman exe zoneの管理者 GreigaMaster氏にコンタクトをとってみました。
So Battle Network 1-5 probably wont be playable using the link cable. Unfortunately as far as I know, the way the link cable works for this game it can only send 2 bytes at a time and has to do this at least once if not more per frame. This is not a problem for the real link cable normally since it is near instant in real life but when emulated it has to be sent over your network to someone else and back which can take too long and cause the game to drop under its standard 60 frames per second. The wireless adapter mode doesn't have this problem in battle network 6 since the wireless adapter has some expected latency so they probably built some lag compensation into the game for that mode. As far as I know the only solution to make Battle network 1-5 playable is to have both players on the same local network, thus lowering the latency, or porting all the wireless adapter functionality from 6 to 1-5.
Same with Starforce 3, how well it plays is going to depend largely on the latency between both players.