にもかかわらず・ながらも: the difference
にもかかわらずN2
Meaning
Despite, In spite of, Regardless, Nevertheless
Past papers
Tested 2 times in past papers
Example
勘違いしたにもかかわらず、彼は一切謝らない。
Even though he made a mistake, he will never apologize.
ながらもN3
Meaning
But, Even while, Even though, Despite, Although
Past papers
Tested 5 times in past papers
Example
すこし狭いながらも楽しい我が家。
Although it is a bit small, it is a happy home.
How to tell them apart
「にもかかわらず」: hard written style; news, editorials, reports.
「のに」: the everyday one; complaint comes through most directly.
「ながら（も）」: the same person is in some state and yet does something contrary to it.