Discord servers

Mega Man Leaderboards

Classic Mega (Speedruns)
Mega Man X Community
Mega Man Zero
Mega Man ZX Dream Team
Battle Network & Star Force

Wikis

http://megamanrta.wikia.org - Mega Man 1-10, Rockman & Forte and X1-6

Other

https://goo.gl/7V5ER9 - Classic Mega Man RTA compendium