So here are some Last Story Spirits i came up with, i'll post more ideas when i think of their concepts.
Lowell
Opponents:

(Advent Blue Palette)
Stage: Hyrule Temple(Battlefield)
Rules
-The Stage is covered with an Ice Floor
-the enemies attacks have increased power for a little
a Support Spirit that makes you immune to Ice Floors and takes up one slot
Origin:Cloud's Advent Children hair is slightly similar to Lowell's, The Ice Floor is a reference to his Ice Attacks.
Music:Order(Normal Battle One) from The Last Story
Yurick
Opponents:

(Blue Coat)
Stage: Pirate Ship
Rules
-The enemies magic abilities increased power
a Primary spirit that increases PSI Abilities and takes up two slots
Origin: The Pirate Ship is a reference to Yurick's father being a pirate and his chapter.
Music: Chaos(Normal Battle Two) from The Last Story
Syrienne
Opponents:

(Cherche Color)
Stage: Hyrule Temple(Battlefield Form)
Rules
-The enemies aerial and neutral attacks have increased power
-Items will occasionally spawn(Cup of Tea)
a primary spirit that takes up 0 slots
Origin: The Tea drinks are a reference to Syrienne's love for wine.
Music:Order(Normal Battle One) from The Last Story)
Mirania
Opponents:

Stage: Gaur Plains(Hazards Off)
Rules
-the enemy heals herself
-you get a flower on your head.
a Support spirit that Auto heals and takes up two slots
Origin: Mirania is a healer which makes sense and the flower head is based off her Leaf and Silence Skills sorta
Music: Chaos(Normal Battle Two) from The Last Story
i hope i got the characters right.