It is possible, however, Mald's Block Game is more of a loose collection of plugins with some very minor custom ones slid in, and a ton of yaml config files on the side.
His "game" is closer to what most rp/adventure servers do already, it's nowhere near what big leagues like Hypixel do, where they have server clusters and use custom plugins for everything.
Some of the many plugins he's repacking as his own game