Hilaria Baldwin's standing by her man -- after a Trump impersonator tried to get under Alec's skin, it's Hilaria who chased the guy down the street ... according to the troll himself.

We got comedian Jason Scoop Tuesday in NYC, where his harassing confrontation of Alec went down, and went viral after he posted it. If ya missed it, Scoop hurled over-the-top zingers at Alec while impersonating Donald Trump Sunday night, provoking a furious response in which the actor threatened to snap the comic's neck.

But, Scoop claims one of the wildest parts of his interaction on the street wasn't caught on camera. He says after Alec erupted over Scoop's jabs about the "Rust" shooting death of Halyna Hutchins, Hilaria came swooping in to protect her hubby.

Jason claims Hilaria sprinted in high heels and lunged at him in an attempt to grab his phone. But to his chagrin ... he says his cameraman missed capturing the footage.

As far as his interaction with Alec, Jason admits he was genuinely nervous after AB got right in his face and threatened violence.

Scoop's jokes definitely crossed a line, but he defends his bit by pointing out Alec mercilessly mocked Trump for years on 'SNL' ... and Scoop himself is a big DJT fan.

Ultimately, the Trump-alike got the big reaction he was looking for -- from Alec and folks online -- but we're guessing he won't be messing with Mr. or Mrs. Baldwin again.