Your cousin's wife is not related to you or to your daughter - unless your daughter marries their son or your wife is related to your cousin's wife.
If your daughter is also your wife's daughter, your daughter and your wife's first cousin are first cousins, once removed, otherwise they are not related.
Your niece and your daughter are first cousins. Your daughter and the daughter of your niece are first Cousins, once removed.
They are second cousins
The children of siblings are first cousins, so your daughter and your brother's daughter are first cousins to each other.
Your cousin's wife is not related to you, so her cousins is not related to you unless she has some family connection to you besides being the wife of your cousin.
They are first cousins.
Is your wife the mother of your daughter? If not, the two are not related and could get married. If she is the mother of your daughter, or has adopted her, she would be considered a first cousin. In many places, they could get married without any problem, but check your local laws as some places do not allow first cousins to marry.
Your daughter and your niece's daughter are first cousins, once removed.
If you are close to your step-brother, or to his wife, you can call her your sister-in-law. If you are not close, you can call her your "step-brother's wife."
Phoebe and Hepzibah were cousins. Hepzibah was the daughter of Phoebe's uncle.
Your son and your niece are first cousins. Her daughter and your son are first cousins, once removed.
Your niece and your daughter are first cousins to each other.