I don't know for sure who Tomo is in this context. It could be the name of a person who is the translator or the founder of the translation project related to these novels.
A 'tomo graphic novel' is a form of graphic storytelling. In a tomo graphic novel, you'll find a combination of illustrations and text that work together to convey a story. The illustrations are not just decorations but an essential part of the narrative. They can show emotions, actions, and settings in ways that words alone might not be able to. Some popular tomo graphic novels have been adapted into movies or TV shows, which shows their broad appeal. These novels can also introduce readers to different cultures and perspectives, as they can be created by artists from all over the world.
I don't think so. There haven't been any official announcements or indications that the HxH manga will continue. But you never know, maybe there'll be a surprise in the future.