After putting the nymphs next to each other, I noticed that they didn't just recolor the sprites. For anyone interested, here is what I noticed.
Edit: Thank you to everyone who pointed out things I missed!
Both versions have scales, but the scales are more pronounced on the nymph. The Light sprite's orbs were shaded to look more like bubbles for the Bubble Nymph. The water nymph was given a design resembling peregrine on her wings.
Rocks were added to the nymph's body. The boulder nymph has more lines in her wings than the Lightning sprite.
The nymph was given a flower. Designs were added to her skin, and her skirt now resembles leaves.
The fiery streak on the Fire sprite was removed, and the magic nymph has a new pattern on her skin.
The book in the snowflake nymph's hand has the Arcane symbol and designs removed, replaced with a bit of ice on the book. She has a few markings on her chest (credit to @KaioticWolf and @Kibble). The snowflake nymph was given more highlights, making her skin appear icy. (credit to @/Kibble)
Not much was changed for the cloud nymph. She has a few swirls added.
The design on the Ice sprite's body was removed. The ichor nymph has a new design on her face, and ooze dripping down her body.
The cinder nymph has striped markings on her legs and tail. Her oil drips over her arms, not just from them (credit to @firewyrm2018). Multiple users have pointed out that her goo is shinier, since it appears to be oil.
The electric nymph has bands on her body and lightning added.
The sparkle nymph has runes and designs on her wings added, and, of course, sparkles.
Spots and lines were added to the blight nymph's flowers and wings to make them appear decayed. She also has a vein texture on her legs (credit to @Shinyumbreon).
Have I missed anything? Are most recolors like this, or did they do more for the nymphs?
Edit: Thank you to everyone who pointed out things I missed!
Both versions have scales, but the scales are more pronounced on the nymph. The Light sprite's orbs were shaded to look more like bubbles for the Bubble Nymph. The water nymph was given a design resembling peregrine on her wings.
Rocks were added to the nymph's body. The boulder nymph has more lines in her wings than the Lightning sprite.
The nymph was given a flower. Designs were added to her skin, and her skirt now resembles leaves.
The fiery streak on the Fire sprite was removed, and the magic nymph has a new pattern on her skin.
The book in the snowflake nymph's hand has the Arcane symbol and designs removed, replaced with a bit of ice on the book. She has a few markings on her chest (credit to @KaioticWolf and @Kibble). The snowflake nymph was given more highlights, making her skin appear icy. (credit to @/Kibble)
Not much was changed for the cloud nymph. She has a few swirls added.
The design on the Ice sprite's body was removed. The ichor nymph has a new design on her face, and ooze dripping down her body.
The cinder nymph has striped markings on her legs and tail. Her oil drips over her arms, not just from them (credit to @firewyrm2018). Multiple users have pointed out that her goo is shinier, since it appears to be oil.
The electric nymph has bands on her body and lightning added.
The sparkle nymph has runes and designs on her wings added, and, of course, sparkles.
Spots and lines were added to the blight nymph's flowers and wings to make them appear decayed. She also has a vein texture on her legs (credit to @Shinyumbreon).
Have I missed anything? Are most recolors like this, or did they do more for the nymphs?
