Chief is going to win this hands down. He's just too good against a Regular Predator. They've got nothing on them that he hasn't faced from tougher enemies. Even the Super Predators from the 2010 Predators movie aren't going to cut it. The Genetically modified Assassin from the 2018 Predator movie will give him a better fight as it WAY stronger than a Regular Predator and even Super Predators. Its virtually immune to bullets due to its deployable exoskeleton...And its also a Bad blood, so its tactics will be harder to predict, but Chief has faced worst. And really, the Assassin was a huge disappointment as he was taken down by a regular guy with no special equipment.
The only way I see any Predator winning this is if you give Wolf the Predator Killer armor. And then if and only if the Armor isn't a piece of unfinished junk as it apparently turned out to be in the follow on comics. Wolf I think is the only real Predator aside from Jungle Hunter that has the skill, but both are lacking in the strength, equipment and the means.
That being said. This has never deterred the Yautja. Ever.
They will study their new Prey from afar and develop new technologies or allow more military based ones to be used in the hunt (apparently the gear they hunt with is their equivalent to civilian hunting gear that's very obsolete). While they're at it the Yautja will now learn of other species to hunt like the Covenant races. This shit will make them as close to giddy as school girls, with the anticipation of it.
Fun times in the Halo universe from here on out, let me tell you.