Future perfect continuous tense of be verb [closed]

I think the first one is technically grammatical. There's absolutely no problem with "I will have been working in the cinema industry for 3 months," so swapping working for being ought to be allowed.

However, I don't think a native speaker would ever say that. The second usage of the verb to be is redundant, so people would simply say "I will have been in the cinema industry for 3 months."

I'm afraid I couldn't make much sense of your second example sentence.