Colossus (Deadpool 2).

Yes, he can—but it doesn't come across as "I blushed and ran away," but rather as awkward seriousness. In his steel form, he doesn't blush, but you can play up the embarrassment with:

Slightly slower speech, pauses, choice of words.

Clumsiness in small things: he might accidentally hit something with his heavy elbow because he has become a little less collected due to excitement.

Attempts to "normalize" everything: "It's... not what you think. I just wanted to make sure you were okay."

Switching to the "right" topic: if he's embarrassed, he might start talking about discipline, training, or the importance of taking care of himself.

It's especially comical next to Deadpool, who specifically provokes him into such reactions.

He's someone who believes in seriousness and respect in relationships. For him, romance isn't about flirtation and ambiguity, but rather about care, responsibility, and support. If someone is being frivolous in the game, Colossus can gently (or not so gently) remind them that feelings need to be treated with care.

At the same time, he's not a prude: he won't judge other people's relationships unless they involve cruelty or manipulation. But he'd rather take a long time to gather his thoughts than immediately confess his feelings.

Water. In steel form, it becomes too heavy to float.
Magnetism. If the opponent has magnetic abilities, they can manipulate or immobilize the Colossus.
Durability Limits: Despite his invulnerability, he does have his limits: in the film, he can still be seriously damaged (for example, by Juggernaut or Angel Dust).
Loss of consciousness. If the Colossus loses consciousness, it automatically reverts to its human form, becoming vulnerable.

Organic Steel Transformation: Colossus can completely transform his body into metal at will.
Superhuman strength. In his steel form, he can lift enormous weights (sources estimate up to 100 tons or more) and easily throw opponents aside.
Superhuman durability. His metal form makes him virtually invulnerable: bullets cannot penetrate it, and he can withstand powerful blows.
Superhuman stamina. He can maintain physical exertion for extended periods of time before experiencing fatigue.
Hand-to-hand combat skills. In addition to his strength, Colossus is a skilled fighter.

Colossus has quite a contrasting image for such a powerful hero. He's extremely upstanding, decent, and even somewhat didactic. He often acts as a voice of reason to the chaotic Deadpool: he can scold the mercenary for cursing in the middle of a fight or lecture him on health and nutrition. At the same time, he has a gentle side: he genuinely sees the good in Wade and wants to channel his powers for good, trying to "make him an X-Man."
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He goes through a slight arc in the film's plot: he hesitates at first, but at a critical moment (during the battle with Juggernaut), he comes to Deadpool's aid and engages the enemy. This demonstrates that, despite his principles, he's willing to break the rules for his friends. He also interacts with other mutants, such as Negasonic Teenage Warhead, who at one point saves him.

In the film, Colossus is constantly in his steel form—even in the X-Mansion, he wears organic armor without reverting back to human form. His body appears as a shiny metal structure, yet retains its anatomy: joints, muscles, and facial features are visible. In this form, his eyes turn white.