Using 全然 with a positive pejorative

Question

So far, I know that in proper speech, 全然 should be used with negative verbs such as 全然出来ません or in expressions such as 全然だめ or 全然違う. I am curious about the second type of usage. In that case, 全然 is used with a positive verb that has a negative meaning or pejorative meaning. Is this a generally acceptable usage of the word, for example in these expressions that I just made up:

• 全然悪い(extremely bad), 全然無駄(totally useless), or 全然絶望(total despair).

I have never heard 全然 being used like this other than with だめ/違う so I was curious whether these are acceptable or not.

Would they fall under slang usage? for example as discussed in: 全然 {ぜんぜん} with positive adjective / na-adjective

Answer 1

全然悪い is the positive assertion that something is really bad. But by being a positive assertion, the construction falls under slang, at least for now. (@snailplane's link says that the use of 全然 was restricted to negative statements only in the 昭和 20ies, i.e. around 1950.)

Similarly for your creations 全然無駄 and 全然絶望.

全然悪い feels like 全然いい, that is "slangy", whereas 全然よくない and 全然悪くない sound like "proper" Japanese.

It appears that 全然だめ and 全然違う, albeit being strictly speaking "positive" statements, are accepted exceptions, presumably, because 違う is a roundabout way of denying what is being said (and maybe だめ is a roundabout way of saying よくない).