A plotline could start with Frieza hearing about Broly's power and being jealous. He then devises a plan to ambush Broly. But Broly, being extremely perceptive in his own way, senses Frieza's approach and is ready for the fight. As the fight progresses, Frieza realizes that Broly is much stronger than he expected and has to use all his dirty tricks to try and win. Or perhaps the plotline could involve Broly being captured by Frieza's forces, and then Broly breaks free and goes on a rampage against Frieza and his minions.
One of the main themes is the clash of generations. Goten represents the new generation of Saiyans while Frieza is from an older, more menacing era. This creates an interesting dynamic. Survival is also often a theme, as Goten has to fight to survive against Frieza's brutal attacks. Additionally, the theme of justice can be seen, where Goten is fighting for what he believes is right against Frieza's tyranny.
I don't know for sure. It might be a complete fabrication or have some roots in reality. You'd have to look into the background and the source of the story to find out.
A possible fanfiction could focus on a group of Saiyans who are trapped in a dimension where they can only watch the Goku vs Frieza fight on repeat. They start to notice small details in the fight that they hadn't before, like the exact moment Goku's power level spikes or how Frieza is trying to adapt his strategy. This newfound knowledge could then be used by them in some way when they eventually break free from that dimension.
Trunks would also be interested. He has his own experiences with fighting powerful foes and would be eager to see how Goku, a great Saiyan warrior, fares against Frieza. Also, the younger Saiyans like Goten might be interested. They've heard stories about Frieza and would be excited to see their father or other Saiyan heroes in action against such a notorious villain.
Well, 'Goten vs Frieza: The Final Confrontation' is a really interesting piece. It shows how Goten uses his unique skills and training to take on Frieza. And then there's 'A New Hope for Goten Against Frieza' where Goten has to overcome some internal doubts as well as Frieza's powerful attacks. You can usually find these by simply searching on the major fan fiction platforms.
Frieza might initially be shocked. He's used to being a feared and powerful being, and the idea of having a family is very foreign to him. So he could be in denial at first.
For Yamcha, you can focus on his growth from being a bit of a comical character to a more serious and respected fighter in the context of his relationship with Frieza. Maybe he learns from Frieza's cold and calculating nature how to better strategize in battles. For Frieza, his development could be about him learning to care for someone other than himself. He could start to see Yamcha as an equal, which is a huge shift from his usual superiority complex.
Then, introduce some shared experiences. Maybe they get trapped in a strange dimension together. In this new and dangerous place, they have to rely on each other's strengths. Goku's physical power and Frieza's cunning could be the keys to their survival. As they go through these experiences, they start to see each other in a new light and their relationship begins to change.
Yes, there are likely 'Bardock Kills Frieza' fanfics out there. The Dragon Ball universe has a huge fan base, and many fans like to create alternative storylines. You can try searching on fanfic websites like FanFiction.net or Archive of Our Own.