I am not a lawyer. Having been sued for legal fees, I can add that if you have family money, the court can take that “separate estate” into account when deciding whether or not to award legal fees. If you have a lot of family money in your name, the judge may not award you fees.
If you have no money of your own, you are likely (in my limited experience) to sue successfully for legal fees for post-separation support, alimony, and child custody lawyer actions. When determining fees, the judge will look at the lawyer’s bills for all of these actions and decide whether or not he/she thinks the lawyer’s charges are reasonable.
Also, I believe that if you are flat broke, you can sue your husband immediately for Post-Separation Support. The courts don’t want to see your kids destitute. Good luck.