Can one create a cipher with two meanings? Not two layers, two phrases in the same cipher in the way that it would have a meaning X, for example, if deciphered using Transposition cipher and meaning Y if deciphered with the Playfair chipher. Is it possible?
This is possible, and it's called deniable encryption. The idea behind this type of encryption is that if you are required (e.g., under subpoena) to provide a key to decrypt your ciphertext, then you can provide an "alternative key" that decrypts it to something else.
However, this is complex, and you cannot do it by hand. In general, it's difficult to do, even by machine.