Sea dwarves as a playable race

This is another sample mixed-ancestry ethnicity for the Sealands. It was created using the Ancestry & Culture expansion, and based on this homebrew dwarf subrace.

Homebrew

sea dwarf

Like the river dwarves, sea dwarves are not a dwarvish sub-ethnicity but a mixture of hill dwarf and elf—sea-elves, in this case. There are sometimes a few to be found in Malfa, because they trade with the Maveren; they are the Maveren's source of sea silk, and some other goods from under the sea.
Sea dwarves form a single ethnicity and cultural group, found in the western Hallic Seas. They have a reputation as level-headed and businesslike. If there are sea-dwarf towns, it's unclear where they are; they can spend many years at sea, both on it and under it.

ability score increase: Constitution +2, Wisdom +1

age: 250 years

Size: Medium

speed: 25ft

Languages: Common, Aquan

race features:

Rower's Resilience. Advantage on constitution saving throws to prevent exhaustion.
Child of the Sea. You can breathe air and water, and you have resistance to cold damage.
Tool Proficiency: Choice of artists tools from Smith & Brewer, dropping Mason Tools and adding Carpenter Tools, Cartographer Tools, Navigator, and Woodworker
Shipshand. You have advantage on tying and untying knots regardless of complexity; you are proficient with vehicles (sea).
Sea Raiders Weapons: Long sword, Short Sword (Seax Knife), and Shields

Sea dwarves average about 5 feet tall, and are generally more slender than river dwarves (though stockier than elves). Their skin has a bluish tint; their hair tends towards green, blue, and black.