Sole custody is not common these days except for single mothers.
see links
Yes, if she has sole legal custody. Not necessarily, if you have joint legal custody. Definitely not, if you have sole legal custody.
Yes, because she has SOLE custody, so you have nothing on the kid legally.
She has sole custody, but he can file an injunction. See link on what to offer
See Link BelowChild Custody- Can Fathers Win
Not if there's court access rights. see links below
Your ex-wife has Parental Responsibility (PR) for her children irrespective of your "sole custody". PR are all the rights, duties and obligations of a parent, including a right to have a say in the important dsecisions in the childrens lives. In the exercise of that PR she can seek information for the children's doctor/school etc
If she doesn't have sole custody, no she can't. And both parents have to sign for a passport, if that helps.
see links below
It will be difficult to maintain a relationship with your niece if the ex-wife has sole or primary custody and you end your friendship with her. Why not simply stay on good terms with her?
wife
per my knowledge a child born during the marriage is both party's child as where he may not get full custody he maybe able to get join custody
Well if you can live with your wife having sex with another guy, then get writing the adverts that will let her experience another man. It is wonderful to watch your wife orgasm as a result of another guy pleasurering her in the place you normally have the sole use of.