Learn English – Is “wait up!” considered correct English

Hyperbaton correct is indeed—from the Germanic side of the ancestry of English, a holdover must I'd wager it be—though usually archaic it is considered, and thus poetically and dialectically it is used. To see it with objects quite unusual it is, as in:

One swallow does not a summer make.

Rather more common it becomes when prepositions more involved do themselves become.

Some rise by sin, and some by virtue fall.

—Escalus in Shakespeare's Measure for Measure, Act II, Scene 1

And poetry let us not forget:

I will arise and go now,
And go to Innisfree,
And a small cabin build there,
Of clay and wattles made;
Nine bean rows will I have there,
A hive for the honey bee,
And live alone in the bee-loud glade

—W. B. Yeats, The Lake Isle of Innisfree

Inversion of noun and adjective is a form of hyperbaton most common: it describes with force a thirst unquenchable, a hunger insatiable, a passion so wild it moans “word order be damned!”; to bolder wax (and more archaic seem), consider the object to move afore the verb, and thy speech merrily to lilt and gaily prance allow.

The phrase "I can't hardly wait" is incorrect.

I suspect it is the result of a confusion between:

I can't wait

and

I can hardly wait

which are both correct.

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The phrase

I can't hardly wait

doesn't make sense: it would mean "I don't find it hard to wait", which is probably not what is meant.

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Probably adding to the confusion is the 1998 teen movie "Can't Hardly Wait". It is possible that the title itself was picked up because the expression is in vogue in American high schools although I did not find any confirmation for this hypothesis.