I'm not sure if you want spoilers so, just in case, a bunch of spoiler space:
. . . . . . . . . . . . . . . . . . I'm 99% sure it's not Steve, alas. It's the 50's Cap, who is horribly burn scarred and was preserved and healed (enough to live) by Doctor Faustus, who has now brainwashed him into thinking he's the "true" Captain America and that Bucky is unworthy of the title and must be killed.
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I'm 99% sure it's not Steve, alas. It's the 50's Cap, who is horribly burn scarred and was preserved and healed (enough to live) by Doctor Faustus, who has now brainwashed him into thinking he's the "true" Captain America and that Bucky is unworthy of the title and must be killed.