It depends what you are saying. For example, it's correct to say this: "Walk in a straight line unless otherwise directed". It is not correct to say something weird like "Well call me unless otherwise you don't want to" or something. But it can be done.
This is not correct grammar. The correct way to say this would be "Unless we hurry, we will be late for the show." You would not say anything if you were not going to be late.
Never, unless you use unproper grammar.
Unless otherwise unless=unless Otherwise=reverse of what it is (reverse case from its original case) so if we are talking like, DON'T GO THERE UNLESS OTHERWISE it means DON'T GO THERE UNLESS OTHERWISE(IT IS REQUIRED TO DO)
On the planet unless you're a miner
No They are not . They have confirmed they are just friends. Unless they say otherwise . No.
"And so are you" is grammatically correct used in an otherwise correctly structured sentence.
No, it is not correct. The correct phrasing would be "For the last two years."
No, the correct phrasing is "on weekends" or "at the weekend."
The correct spelling is "otherwise" (in an alternate circumstance).
Yes, as an incomplete sentence, followed by a prepositional phrase. Otherwise, "Who did you expect?" is standard.
No it is not unless it is in the context of an indirect object where "to" or "for" plus the above phrase is grammatically correct. In addition, it is better to say "my partner and I" although that can lead to rather convoluted sentences.
Depending on the sentence, not unless could be the correct form.