When Square Enix put together Kingdom Hearts HD 1.5 Remix they made some tweaks to make Kingdom Hearts control more like Kingdom Hearts II and included all of the bonus content from the Final Mix version.
Final Fantasy X-2 was re-released with extra content in Japan too as Final Fantasy X-2 International + Last Mission. This version of the game adds three more dress spheres (festivalist, psychic, and bare) and a whole extra "Last Mission" episode that takes place three months after the events in Final Fantasy X-2. Last Mission has a massive tower to climb and conversations that act as an epilogue for many characters in Spira. Famitsu specifically says whether Last Mission has been included or not in Final Fantasy X-2 HD Remaster is "undecided." Perhaps, Square Enix will release this as DLC?
Final Fantasy X-2 International + Last Mission also has Creature Create mode where you can capture and train monsters. It’s basically the source of inspiration for Final Fantasy XIII-2’s battle system where the third character can be a monster or if various captured characters like Snow.
Famitsu says the FFX-2 remaster is based on the North American version
of FFX-2 International + Last Mission
Creature Create was not in the original released and added in
The status of the "Last Mission" which takes place 3 months later is undecided
for the HD remaster version