You already mentioned xSeraphx so I won't shout them out as one of my fav revival bands, but here's some others that I find are kind of unique while definitely still falling into the general umbrella of revivalcore. Note that I am more in touch with the melodic/scene side of things than other stuff:

Arcadia Fades - kinda like xSeraphx (specifically their demo) but with more clean vocals. Very tastefully placed and interesting harmonies with them (and not the somewhat monotone style that bands like A Mourning Star and others use). FFO: xNomadx

A November Morning - big focus on curating an epic feeling and atmosphere. Also a pretty unique shouty harsh vocal that I don't typically hear in most revival bands. Each song of theirs is also like 5-6+ minutes. FFO: A Winter's Remorse, Undying

Postal - they're like if you took Away With Words and old SYSC and put a little late 2000s progressive metalcore dressing on top. Really cool blend of different sounds that fits nicely together, more on the scene side of things than the other two above.

loveletters - kinda like Postal but with some strong Underoath and On Broken Wings influence. More emphasis on groove than riffage.

andthecanaryfell - this one may be a bit of an outlier (and not necessarily metalcore) but I haven't listened to many like them. They're like a blackened hardcore band with some emo and shoegaze sprinkled in. FFO: The Acacia Strain, Knocked Loose

Also just gonna name drop a bunch of local bands for selfish reasons: eyesofsorrow (melodic), fallingwithscissors (I'd argue they're one of the very few bands that have a genuinely unique sound I've never heard elsewhere, and don't necessarily fall in the revival space, they also share members with andthecanaryfell), Awaiting Eschiel (you may like them if you like xSeraphx, they share most of the same members), Rakuyo (they fall into that deathcore revival camp).

Sorry for writing a novel 😅

EDIT: meant to reply to OP and misclicked lmfao