I think that PV is more focused on helping women more so than men because that is the stereotypical case. However, I do not doubt that PV stems from women abusing men as well. In regard to men being victimized, I feel that they are less likely to reach out for help for a few reasons. One of these being that it might be embarrassing for them. Men are thought to have to be the stronger sex who is more dominant. I think this is why it is so hard for them to get help when they do reach out. I think that more females are victimized because it is an easier story to believe. The women are less scared to speak the truth and I think the world expects it to be women who are victimized. I think that Patriarchy theory could be a cause for this. The men typically make more money, which we have learned makes them have power over the women in the household. This makes sense to be correlated to women being more abused than men.
Issues that could arise from children witnessing PV could be the way that they view relationships. Children who witness PV are more likely to be more aggressive and be involved in PV later on in their own life. For example, a little girls who sees her father abuse her mother might be more likely to get into an abusive relationship with a male. This is because to her, this is normal. A little boy who see his father abuse his mother will be more likely to be the abuser in the relationship because he grew up with that and, again, will think it is normal.
I don't know that it affects either gender more directly, but if I had to choose, I would say men get more mental trauma from watching their mom being abused (for example). I say this because in society today, women are told to speak up and are more welcomed when they are going through something. But men are told to shut up and not say anything. They are told to "Man up" and such, so they internalize their problems, which leads to trauma not being resolved. Women are more likely to get help when they reach out for it, which makes their issues less internalized and manageable.
Some sources to help victims of PV are the police, hotlines, and shelters.