It wasn't until a 3rd party company agreed to translate the game for Capcom that it saw international release and Knight Man's designer got his special copy.
It wasn't just "a third party", it was Nintendo of America itself. Since Wind Man and Knight Man were designed by North Americans, Nintendo took it upon themselves to translate and release the game in North America. This makes the box and manual for the game kinda odd when compared to the other MM games. It looks more like a late-NES first-party title from the box design, and CAPCOM is only mentioned once in small text in the first page of the manual. (Also, Mega Man's the most on-model he would ever be on the boxart until MM8. The people at Nintendo of America knew how to draw Mega Man better than the people at CAPCOM USA)
Why does Dr. Light need to time travel, anyways?
In the games, time travel is only used twice, in Mega Man II, and Mega Man - The Wily Wars. In II, Wily got ahold of an experimental time machine at this "Chronos Institute" place. Dr. Light didn't even make it
And in Wily Wars, it's not specified how, but Wily was able to travel to the times of MM1, MM2, and MM3, to mess up the timeline, and Dr. Light just builds another time machine out of nowhere so that Mega Man can go stop him
So Dr. Light needs time travel so that Mega Man can stop Wily from screwing up everything
And going back to the Knight Man thing, I'm happy there is one Robot Master who was designed by a Canadian, haha
Even if Knight isn't really one of my most favourites