Aquarius [FABRIC/FORGE]
New: The mod now uses Architectury architecture, making it a dependency, but one file works for both Forge and Fabric. Improved the air flight mechanic - now you can fly through 1-block high spaces, and stopping is smoother, resembling exiting water.
Hello! My name is Acro, and I've taken on porting Aquarius to version 1.16. In the future, I plan to add new features such as hostile ocean mobs, useful applications for corals and sea grasses, and more fish types. For now, I present to you:
Aquarius
Expanding the capabilities of version 1.13 content
Or a text description:

From left to right:
Guardian Sight I-IV: An enchantment for tridents that allows firing guardian-like beams by holding right-click.
Channeling II-III: Enhanced levels of Channeling enchantment that allow striking mobs with lightning even without thunderstorms. Channeling II works during normal rain, and Channeling III works anytime.
Chorus Conduits: Allow swimming in the air while holding the jump button. Crafted from water with purpur or purpur pillars instead of prismarine. Also adds the Atlantean potion effect, available only with the chorus conduit. Crafted from one conduit and two shulker shells, similar to a shulker box. (Based on a video by Grian) Also enables using Riptide outside of water.

Example setup of a chorus conduit
Prismarine Rods: Used for crafting and repairing tridents. Made from two prismarine shards and one prismarine crystal. Tridents are crafted from two prismarine rods and three quartz.
Flippers: Grant Dolphin's Grace effect in water, but slowness on land. Crafted from two leather and two scute.
Report issues or suggest translations on my mod fork on GitHub.