Ambiguity of ‘just not’ or ‘not just’

tinsoldier: not just a pretty face — Noun: 1. (sometimes humorous) Someone who is more intelligent, talented, or emotionally complex than might be assumed., 2. (idiomatic) Something that is more useful, versatile, or intrinsically valuable than might be assumed. https://en.wiktionary.org/wiki/not_just_a_pretty_face

Not just a pretty face.

Sorry, no job for you. You're not just a pretty face.

‘Not just a pretty face’ is ambiguous?

There is apparently the same ambiguity in the corresponding Japanese expression.

"He's not just the enemy."

All the others are, but not him.
Or, He’s the enemy and many others are too.

Am I wrong? Is it more correct to say,

Sorry, no job for you. You're just not a pretty face.

Rather than,

'Sorry, no job for you. You're not just a pretty face.'

In which case, the ambiguity is in the Japanese, but not English.

I think both could be used to express lookism.

Disambiguating with,

The enemy's just not him.
The enemy's not just him.

Perhaps.

In Japanese, disambiguating is done by marking the enemy as topic, I think I read.