Pokemon Cosmos : Do not think Pokemon Cosmos is a ROM hack of any Pokemon game. Instead, it is a fully developed Pokemon game with RPG Maker XP.
Pokemon Sigma Version is from RMXP for the first time almost a year ago, RMXP and Pokemon Essentials were perfect substitutes.
Pokemon Style Battling (Untitled Project) is the name of a game with the Pokemon ideas but in a newer style. Of course it comes from PC platform with the support of RPG Maker XP.
Pokemon Serpentine is a game created from RPG Maker XP and included five different regions with the Pokemon Essentials pack.
Pokemon Nightmare : Much later than its predecessors, Pokemon Nightmare also was brought back to active with the support and the calling from the original team. RPG Maker XP platform is their favorite tool to do this.