Regarding the spell schools, every spell in the D&D game can clearly belong to one of following spell schools, when each school is defined as follows.
Conjuration: Astral Plane with Celestial, summoning, thoughts and dreams.
Dunomancy: Ethereal Plane with Fey, force damage, gravity, telekinesis, flight, quintessential ether as the fifth element.
Necromancy: black magic, ethereal Shadow, Undead, astral Fiend, Aberration.
Evocation: Elemental Energy Planes: Air (Lightning-Thunder), Water (Cold), Fire (Fire, Radiance, light, darkness), with primordial matter (Acid).
Transmutation: Material Plane, Elemental Earth Plane, Plant, making objects (stone, metal, wood, ivory, etc.), Beast, shapeshifting, healing.
Illusion: alteration of reality, wish, force constructs, quasi-real objects made out of ethereal force.
Enchantment: mind magic, telepathy, charm, fear, morale, alertness, domination, subjective mental phantasm.
Divination: space-time, such as precognition, timelines, fate, blessing, luck, and such as teleportation, chronomancy temporal distortion.
Abjuration, in addition to an other school: spells that have a protective purpose, such as shielding, warding away foes, healing, resurrection.
Execration, in addition to an other school: spells that have a hostile purpose, such as debuffing, targeting, damage, preventing resurrection.
Marshalcy, in addition to an other school: spells that enhance positioning or impede it, such as speed/slow, teleport/wall, flight/grounding.
Apparence (!), in addition to an other school: spells that avoid detection or detect: such as invisibility, disguise, true sight, locate target.
Some spells are complex with several moving part, where each part might belong to a different school. Generally, only one part is the main theme. However, some spells work better as belonging to more than one school, especially for the practical purpose of granting access to it in more than one spell school list.
Here, the Transmutation school represents magic involving Earth, Plant, and Beast. These are disparate but are the main of the 2014 transmutations, and are inseparable as substances that objects are made out of. For example, a spear is made of Earth and Plant, and a fur cloak is made of Plant and Beast. Whether medicinal chemicals, herbal remedies, or shapeshifting into a healthy body, healing is mainly transmutations, where even the soul is an aspect of animal life.