The reveal of Marvel vs. Capcom Infinite's Captain America and Morrigan brought an extra surprise: X's First Armor. Though not officially confirmed, it would appear X dons his X1 duds when engaging one of his Super moves. The move in question comes in at 0:32 in the clip above.
I know it's not the best video but it'll make do for now. I'll update this post when Capcom rolls out the official version. UPDATE: Got it!