The non-canonical manga/anime series Super Dragon Ball Heroes, inspired by the popular video game of the same name, has provided a treasure trove of fan service to Dragon Ball audiences, including plenty of new combat transformations and character fusions not seen in the main continuity. Among the fusions introduced by Super Dragon Ball Heroes are the composite warriors Gohanks and Vegeks, both involving versions of Trunks merging with a different Super Saiyan to form a particularly formidable fighter. However, while bringing power to the proceedings, both fusions feel just plain uncomfortable in who Trunks ends up pairing with to create the composite character in the first place.
Gohanks is formed by Trunks and Gohan performing the Fusion Dance. There are three different versions of the warrior, the most notable of these being Xeno Gohanks, a fused fighter serving on Super Dragon Ball Heroes' Time Patrol. Vegeks is formed by Xeno Trunks and Xeno Vegeta using the Potara earrings to fuse. Both fused warriors are far more powerful than their individual Saiyan components, with Xeno Gohanks able to transform into a Super Saiyan 3, while Vegeks is able to destroy the fearsome Xeno Janemba just in a base Super Saiyan transformation -- whereas the rest of the Time Patrol team was unable to previously defeat this alternate vision of Janemba.
What makes these fusions uncomfortable is that both involve Trunks merging with a father figure -- in the case of Vegeta, his actual, biological father -- in order to create a single, composite character. For Gohanks, this is still much more understandable, as Gohan and Trunks are not directly related at all. Future Gohan simply raises Future Trunks in their alternate timeline to survive against the rampaging Androids 17 and 18. There are paternal undertones to that relationship while also providing a mentor-protege dynamic to Dragon Ball Z.
Conversely, Trunks and Vegeta fusing into Vegeks is much more awkward, with Vegeta combining with his own son, even if the union is a temporary one. Xeno Vegeta acknowledges that this fusion is one made out of sheer desperation and will be the only time he and his son do so, with Xeno Trunks agreeing.
The possibility of father and son fusing was previously proposed in DBZ when Goku was looking for someone to merge with using the Potara earrings, as Majin Buu defeated Gohan and absorbed Gotenks and Piccolo. With Vegeta still dead and without his body at the time, Goku assumed Gohan was the only viable candidate left to fuse with as he returned to Earth. Deciding to proceed with this plan, Goku admitted that such a fusion would lead to an incredibly uncomfortable conversation with Chi-Chi, but was spared this awkward scenario when Buu absorbed Gohan and Vegeta arrived on Earth after having his body restored by King Yemma. This led to Goku and Vegeta fusing for the first time with the Potara to form Vegito.
Gohanks and Vegeks are both incredibly powerful warriors and additions to Super Dragon Ball Heroes but are perhaps unlikely to ever appear in the main Dragon Ball continuity. Especially in the case of Vegeks, there's just too much awkwardness surrounding the idea of a father and son fusing, and which would likely bear a considerable amount of consternation from audiences. While Gohanks and Vegeks are sure to have their fans, their omission from Dragon Ball's official canon is probably for the best.
