Note that Allsides exists to present the news as a balance. That's what they're selling. Not that this automatically makes them wrong, but it predisposes their perspective as seeking equal and opposite dichotomies.
Just for comparison, the commonly-cited Ad Fontes chart puts CNN as "skews left" and OAN as "hyperpartisan right".
https://adfontesmedia.com/static-mbc/?utm_source=HomePage_St...
I will note, however, that Allsides is based on the web content, not the TV content. The Ad Fontes chart puts CNN's web and TV presence in about the same place, but OAN's as just "skews right". (More to the right than CNN's left, but given the vagaries of the definitions it's reasonable to put them in the same place.
It's remarkable that they put the OAN web presence slightly to the left of Fox News. Though this puts them just straddling the line of "hyperpartisan": OAN web to the left of it, Fox to the right.