Well,... Sorry about your Divorce but it's obviously going to impact your dating game, Good or bad, I couldn't tell you.
1. When do you disclose this? Prior to meeting up on date, at the date, etc? I wouldn't bring it up right away, Just focus on hanging out and dating the girl/girls and if it comes up then disclose it. If you are looking to just have sex and have a good time then I wouldnt bring it up either unless of course it comes up for example, "I have to go to take care of a few things" and she says "Why cant you stay with me for the night?" then you let it be known, "I have a child that i need to attend to". If she gives you problems after that then she can walk. Also if a chick ever gives you sh*t like "Why didnt you tell me right away!?" You dont need to tell her anything until and unless things begin moving towards a relationship or if she straight up asks "Do you have any kids".
2. Is this an issue that hurts game? I personally couldnt tell you because I have no kids but I have friends in this situation and from what I can tell, the only impact it has is limiting their time with certain activities. They may not be able to hang out all night because they need to care for their child.
3. If it does, how do you minimize the impact of this on dating, game, etc? You need a balancing act of your responsibilities and getting pvssy. You can't really minimize the impact in certain situations, for example, You need to care for your child one night vs she wants to meet up for a date. Your child comes first and therefore can't meet up with her.