Ftg requires kunai to be located, and a user with wind release could easily counter those as well as Minato. Also some noobs are making assumptions and guessing wat Minato should be capable of doing, knowing damn well we haven't seen it done by him. As of what we have seen the only sealing effective against oro would be reaper seal and that kills Minato as well. Ftg could very well be useless (not defiantly) because wind release shinobi would easily counter Minato's kunai.
Minato himself would have to deal with; Minato, 8 branch technique, other snakes and possible Edo. These are all good enough distraction allowing oro for a possible opening, or to simply wear Minato down. Also we havent even discussed wat Oro himself could do. Let's not forget he has genjutsu, poison, sealing, sword (that he can remotely control) and earth clones (if I remember correctly).