Basically yeah, each monsters sould you capture does something different (including the bosses if I recall), so some might be simple fast attacks, some would be shields, others big hard hitting. You could change your loadout to suit your needs. Technique sounds like the wrong word reading it back, moveset might be the better term.

Very early PS3 Japan Studio game.

Trying to keep to the last couple gens (earlier's too easy):

Interacting with a giant AI controlled animal - as the primary gameplay, no less (The Last Guardian)
A full ecosystem of mechanical animals to interact with (Horizon)
Good open world stealth (Far Cry 3 & MGSV) (FP & TP, respectively)
Play, create, share game and world building (MediaMolecule games)
Bring a pulp adventure flick to life (Uncharted)
Bring the Wild West to life (RDR)
Competitive painting (Splatoon, if it counts)
Portal, nuff said

I had seen it somewhere before but dismissed it as a typical JRPG. Now that I looked it up the game definitely looks unique in more than just the combat system. Would the game hold up today?

TLG, Splatoon, Portal, and probably Dreams are the ones that stand out the most for me, as the entire games are dedicated to something entirely unique.

I do like your choices and I would love to hear some examples from earlier generations as well. PS1, PS2, N64, Gamecube, Dreamcast, Xbox. No reason unique ideas if good couldn't be used again today in modern games.

It still looks good, very unique style. Decent enough story. Although I haven't played it in a while so some parts might have aged, I'm not sure, requires sixasix.

Just looked at the store, I think you can still download the demo for PS3.

naval battles in AC3, 4 and Rogue

I also thought about folklore. I also thought the motion controls to capture the monsters were a fun and original thing, very intuitive.

Panzer Dragoon Saga, still no other game like this even today the battle system is an rpg variant of the unique shooting mechanics the series is know for.

E.V.O.: Search for Eden on snes had nice evolution mechanics that I really havent seen since, at least not done in the same way

Not unique anymore but I would say Mario Galaxy is pretty unique