A worthy tribute to Megaman. I thoroughly enjoyed my journey to 100%. Hard mode is hard. I think I'll leave that for another day. Finding all the secrets is tremendously fun. I can't recommend playing this through enough.
Sadly, perhaps the best hook in your game, the presence of all sorts of popular robots, constitutes copyright infringement. I certainly appreciate all the work put into this, and I really did enjoy all the shout-outs and references, but don't be so surprised to see it taken down at some point.
Tips and Tricks: You can reconfigure the controls from the pause menu. Do so immediately. Like Megaman games, you can unlock a character or capsule, then leave without finishing to keep your unlock. You can jetpack upwards, switch characters, and then double jump to reach high places. Try jumping up the left wall at the beginning of the ice level for a fun little surprise. To get to the Lightning Bolt powerup in HQ, you need to S-rank all of the levels, I think. It might be more lenient than that. You can only switch characters when hit-invulnerability has worn off. You will need to use slide (hold down and press jump) to pass certain areas. I believe that sliding is also faster than running, which helps for speedruns (gotta get those S-ranks!). The Mystery Item can give extra lives, health, bombs, or damage you. The capsules which give attack or defense upgrades are given to whichever character you pick it up with. Go back to levels you've completed to farm cash a lot faster. I never really needed to do that much, though. Aperture Science was very hard for me, especially to speedrun. Coyote Tango has two damageable components initially, the axe blade and the lower body. Destroy the axe first to make your life easier, destroy the lower body to detach the upper body, which then enters a different attack rotation. When the reactor opens up, then you can damage it. I'm honestly not sure how to consistently avoid damage here, although generally staying low helps - the legs aren't all that dangerous. When speedrunning Optimus Prime's stage, you need to hold right to go faster. In hard mode, you only get one character (ever, I think), enemies deal more damage, and health pickups and save points are fewer in number.