Here's how you can get some yellow/red mcdonalds colors on certain characters SF6

In the multi-menu, go to options, then Input Event Code. You'll have to type them in manually:

〇McDonald's EX Color (Ryu) M3L4-WJAK-8FCH-6AYV

〇McDonald's EX Color (Chun-Li) CDU9-BBPC-DNQU-98M9

〇McDonald's EX Color (Ken) LFCU-8RYT-7MP9-RH8F

Also, if you can VPN into Japan before launching the game, you can get another bonus color in a News gift pack