Final Fantasy Type-0
While working on "Final Fantasy XV", Tabata decided to make a high-definition remaster of "Type-0" for eighth-generation consoles. Developed by Square Enix and HexaDrive, "Final Fantasy Type-0 HD" was originally announced at E3 2014, and released worldwide in March 2015. After "Type-0"s release, Tabata stated in an interview that he wished to explore the distant history of Orience after the events of the game. Trademarks for "Type-1", "Type-2" and "Type-3" were registered shortly after the "Type-0" trademark, but it was suggested that they were simply a protective measure. During interviews given in 2014, Tabata commented that he wished to work on "Type-1" after completing "XV", and later explained the conceptual "Type" series as a means of publishing "Final Fantasy" games too experimental for the main series. He hoped to continue with the "Type" series if "Type-0 HD" was commercially successful.
Spiritual successor
One example of a spiritual sequel resulting from legal issues is "Dark Souls" by From Software, inspired by "Demon's Souls" by the same studio. The rights for "Demon's Souls", an exclusive title for the PlayStation 3, was held by Sony Computer Entertainment, preventing From Software from making a successor on other platforms, leading them to create a new property with similar gameplay mechanics for the Xbox 360 and other platforms. Another example is "Perfect Dark", developed by Rare as a spiritual sequel to their licensed title "GoldenEye 007". Rare had planned to develop a sequel to "GoldenEye" but lost the license as they were outbid by Electronic Arts. The developers still wanted to complete another spy-based title and developed "Perfect Dark" with a new story but with similar mechanics to "GoldenEye". 
All "Final Fantasy" games in the original series are spiritual successors of the original game rather than being sequels. The first proper story sequel was "Final Fantasy X-2".