Нормально ли спросить "сколько время"?

Нормально ли спросить "сколько время"

If by "normal" you mean "are there people who see nothing wrong with this construct", then yes, there are lots of people who talk like that and see nothing wrong with this construct.

It's not uncommon to hear this phrase in live speech, and it's being mentioned in the corpus as early as 1866, in a direct speech of one of Leskov's characters.

The use of this phrase is, however, discouraged by most style guides. This phrase would not make it through proofreading and copy-editing pipeline of most media which do proofreading and copy-editing.

People, who are taking their clues about grammar mostly from printed media, would treat this phrase as a solecism, "a phrase that transgresses the rules of grammar"

Может это какой-то региональный сленг

As far as I can judge, it's not, it's used all over Russia and other Russian-speaking territories.

In Nizhny Novgorod and its vicinity, the answer to that could be без пять десять (instead of без пяти десять) which is a regionalism.