This is one of the issues I have with going from 3.5 to 5e. In trying to simplify the rules, they have left out details that make it ambiguous.

Here’s the text of the rule from 5:

Three illusory duplicates of yourself appear in your space. Until the spell ends, the duplicates move with you and mimic your actions, shifting position so it’s impossible to track which image is real. You can use your action to dismiss the illusory duplicates.

Then there is detail on how it affects attacks

Each time a creature targets you with an attack during the spell’s duration, roll a d20 to determine whether the attack instead targets one of your duplicates.

If you have three duplicates, you must roll a 6 or higher to change the attack’s target to a duplicate. With two duplicates, you must roll an 8 or higher. With one duplicate, you must roll an 11 or higher.

Then there is detail on how the duplicates defend:

A duplicate’s AC equals 10 + your Dexterity modifier. If an attack hits a duplicate, the duplicate is destroyed. A duplicate can be destroyed only by an attack that hits it. It ignores all other damage and effects. The spell ends when all three duplicates are destroyed.

Then the rule ends by describing how to bypass the spell.

A creature is unaffected by this spell if it can’t see, if it relies on senses other than sight, such as blindsight, or if it can perceive illusions as false, as with truesight.

It does not say that a creature is unaffected by this spell if it is using a spell that does not use an attack roll.

Magic Missile starts with this:

You create three glowing darts of magical force. Each dart hits a creature of your choice that you can see within range.

I would argue that Magic Missile relies on sight, and Mirror Image prevents you from visibly discerning which duplicate is the target. So you can’t “see” which target is the creature and which is the duplicate.

I know I’m in the minority on this topic, and I’ll always defer to whatever the DM decides. Most people feel that, since it doesn’t explicitly include non-attack targeting, that those actions ignore Mirror Image. But I prefer to play to a common sense interpretation of the spirit of the rules. Like if a teammate tries to toss a healing potion to the Wizard, but it shatters on the ground because they threw it to one of the duplicates. Or casting any divination or enchantment that relies on sight should be affected by Mirror Image, even if there is no attack roll.

That’s the logic I was extending to include applying a mirror to the target. But that’s probably too far afield from RAW.