Update:
I was contacted by the cosplayers directly. Their cosplay name is "Tom_Mjcosplay", not "Tom and Jay Cosplay" as I originally suspected. They have a shared instagram account with a bunch more photos. Working on getting more details from them.

Smikimimi Cosplay has posted the video of the Montreal Comic Con Masquerade, where the cosplayers compete in small skits. I can't embed it here, so you'll have to watch it on YouTube. It is timestamped to 29:35, where the Fox and Krystal skit begins.

The Fox and Krystal duo cosplay were entry number 17, in the Journeyman division (just above the Amateur division). Their skit, "How it Should Have Ended", appears to have been a recreation of the final scene in Star Fox Adventures. Fox congratulates his team and Krystal shows off her staff. Not sure who they got to do the voice acting for Fox, but it sounds just like the original voice actor. As for Krystal, her voice was pretty good too, just different.

Krystal shows off that yes, her staff does indeed light up, and very brightly. Both Fox and Krystal's masks have moving jaws. Unfortunately for everyone, the audio system cuts out right as they started getting into the middle of their skit, so we don't know what the rest of the skit was supposed to be. Perhaps they were going to use some of the unused audio from Adventures where Krystal asks for a kiss. Smikimimi Cosplay cut the video until they walked off stage.

It was hard to hear, but it sounded like the cosplayers were "Tom and Jay Cosplay". And that's all I could find out...

OR WAS IT?!

Because while researching this video, I found the actual Krystal cosplayer!

It's Marie-Dauphin Cosplay, who has a Tik-Tok account. There are multiple videos posted with photos and other details about their experience. In the descriptions, we get a much clearer picture of what happened.

• Cosplay Creation Photos - Lots of details about how the Fox and Krystal cosplays were made. The heads were 3D printed and then covered in fur using a duct-tape cutting method to create the pattern. The jewelry was 3D printed as well. With the heads done, they moved on to clothing and accessories. The clothing was made from scratch with a lot of customization. Additional pieces were 3D modeled and printed from scratch. The staff was created by using light saber parts and then a shaft that had blue window tint with gold pattern around it. (Say, that sounds familiar!) The tails were made with internal supports to keep them relatively stiff. And lastly, Fox's wrist armor was made from foam. They have been working on these since January!
• Fox + Krystal Con Photos - A collage of photos of the Fox and Krystal cosplays.
• Krystal Con Photos - A collage of photos of Krystal running around the convention being silly and posing for photos.
• Quick Turn Around Pose - Krystal shows off the suit and staff before striking a quick pose.
• Complete Masquerade Performance - We see the sections that were cut from Smikimimi's video. They were unable to get the audio restarted and had to walk off stage. From the description, after they were unable to restart the skit, Marie was devastated and was crying as they walked off stage. However, the two of them plan to redo the skit themselves at a later date. Marie also says they plan to modify the cosplays a bit and do another con to show them off sometime in 2024.
• Receiving Prize - Krystal and the guy I assume was in the Fox cosplay earlier find out they won in the accessories category for Krystal's staff, and they rush up to the stage to get their ribbons.
• Award Photos - Photos from the awards ceremony where they got ribbons in the accessory category. According to the description, the earlier tragedy had turned to joy as Marie was crying again inside the suit, but this time they were tears of joy.

Looking forward to seeing the full skit! Well done Marie-Dauphin Cosplay!