Alright.
Tsunade vs Kakashi, We have not yet seen full potential of Tsunade, and we have seen a lot to what Kakashi is capable of, and both of them probably have more to show. Kakashi has lightning style, ms and so on. Tsunade got CR and summoning and is incredible taijutsu user, and so is Kakashi. They are boh strong but we have seen pretty much nothing from Tsunade, so she probably has something up her sleeve against mid to long range users. So id say Tsunade with High diff.
Oro vs Kakashi, well kakashi is strong but i think some people overrate him, and Oro is very strong too, even though he propably would have lost to the 3rd Hokage without Edo Tensei, but that does not matter its a jutsu he has. Well if we look at both peoples skills, Oro exceeds kakashi in jutsu, intelligence, experience. Oro with Low-mid diff.
J-Man vs Kakashi: well kakashi has a lot of jutsu and he is skilled. Jiraiya has SM, huge toads and he is a fire-earth style user, id say he can defeat Kakashi on low diff. Jiraiya could defeat him with SM not even if kakashi use kamui, jiraiya is too fast in that mode, and jiraiya probably know all about it. Fukasaku and Shima also has their Genjutsu, which could completely defeat Kakashi.
In personal opinion Jiraiya and Oro would walk all over Kakashi. People overrate kakashi and some people underrate Tsunade. But you cant really compare them at some points.
Best scenario: kakashi vs Tsunade, even though we dont know much about tsunade as or what we have seen.