If your sister is unable to pay for an attorney, the court will force her husband
to pay for her attorney.
I am not aware of any repercussions for waiting to file for a divorce. I do not understand exactly what your concern is.
Concerning the waiting period of a year before getting the divorce, that is a misconception that many people have about the law in New York. That is only about using the Separation Agreement as the grounds for the divorce. If other grounds are used, such as adultery, a divorce may be filed, and judgment ordered immediately without any waiting period.
Leonard M. Weiner, Esq./Divorce Solutions