Well, i'll give my take on that then.
The in-game statistics shouldn't be used for indexing, I don't believe any of that should be used. No uniques, no stats, nothing. None of that is canon to any of the stories, and they vary wildly between the exact same person with the exact same form and power active at the time, because they're different "characters" within the game. For example, Strength (red) Attritbute Demon Meliodas has a passive that increases his crit chance by 50% when an ally of his dies. HP (green) Attribute Demon Meliodas refills his Ultimate Gauge by the amount of orbs the person he kills holds. And Speed (blue) Attribute Demon Meliodas is immune to having his attacks disabled till he has his Ultimate.
All 3 of these characters are literally just Meliodas using his demon magic.
They have no canonical basis. I'd say it's best, if we make profiles for the games, to use strictly the abilities they showcase within their respective stories. The game mechanics are just game mechanics that go on top of the story, but aren't actually a part of any of the stories. Anywhere.
For example, Sigurd's passive within the game itself makes him qualify as part of the Demon race because he wields Legendary Sword Gram. This has no actual canonical basis, he's never stated to be technically a demon because of the weapon, or anything.
I am aware that this changes the indexing significantly, but I believe it's the only way to honestly index these characters without genuinely indexing full on game mechanics.