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.
The plot could start with Bardock having a premonition of Frieza's future actions against the Saiyans even before the destruction of Planet Vegeta. He then secretly trains and discovers a new form or power that allows him to stand up to Frieza. When Frieza arrives to destroy the Saiyans, Bardock reveals his newfound strength and battles Frieza. After a long and intense fight, Bardock manages to defeat and kill Frieza, changing the course of the Dragon Ball universe. This could also lead to new alliances and power struggles among the remaining characters.
There are fanfictions where Vegeta has a spiritual awakening of some sort. He realizes his true potential and his connection to the Saiyan pride. This newfound power allows him to generate a massive energy field around Frieza. The energy field then compresses in on Frieza, crushing him from all sides until he is completely destroyed. This method not only shows Vegeta's power but also his growth on a more spiritual level.
Jiren could still be a tough opponent in the 'vegito tournament of power fanfiction'. His power level is extremely high, and he has great combat skills. Even for Vegito, defeating Jiren would be no easy feat as Jiren has proven his strength time and again in the original tournament.
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.
In crossover fanfiction, Vegito Blue often brings a powerful and exciting element. His character combines the strengths of Goku and Vegeta in a unique way. For example, his combat skills and strategic thinking are enhanced due to the fusion. Writers can use him to create epic battles against various foes from different fictional universes.
One aspect of Vegito and Female Gogeta fanfiction could be the exploration of their unique power combinations. In these fanfictions, writers might create scenarios where they team up against a powerful enemy. For example, they could face a new, extremely strong villain that neither could defeat alone. Their combined strength and different fighting styles would make for an exciting story.
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.
The Super-Reflected Being was a key core card in the Explosive series, and also the most outstanding single card in the Harmonization system. It could be used anywhere from 6 to 9 stars. The Super-Reflectors could be used as synchronization materials. After leveling up, they could summon other powerful monsters at the same time, such as the Flame Paladin Emperor Charlie, the Gun Gun Fierce Dragon, or the Psy Skeleton King Omega. In some Dark Magic Decks, Super-Reflectors were also used to compress the deck so that the key cards were easier to use. Although the strength of the Super Reflectors in the game was very high, to use it, one needed to stuff some useless cards into the deck as a price. All in all, the Super-Reflected was a very powerful and common card, widely used in different card sets.