Here are the different dwarves in my homebrew setting:
1.) Mountain (live deep in Mountains - as PHB)
2.) Hill (Live on/near the surface - as PHB for the most part)
3.) Duergar (Live in the Underdark - per the books, mostly, but their primary culture tends toward duty rather than the more sinister highlights common in other game)
4.) Elemental Dwarves - These dwarves come from my Elemental Plane (I have one Elemental Plane rather than 4/8 Elemental Planes). They Have the same core abilities as most dwarves, but they speak Elemental Languages, they gain resistance to fire and cold, and they gain 2 cantrips and 2 spells from a specific list (all elemental themed - and generally seen as weaker and non-combat). They are the greatest miners of the Known Universe.
5.) Vylons - Twisted by the Far Realms, these dwarves have nightmarish earthen inspired abilities. They gain a fear ability useful once per short rest, psionic abilities (using my house rules), and the ability to return foes to the Earth (if you're in their aura, large or smaller and in natural terrain you make saving throws at the end of your turn. The first failed one reduces your speed. The second grapples you. The third (if the grapple is not broken and you fail the save) pulls you into the earth (restrained). The fourth crushes and begins to suffocate you. Their culture encourages them to be Warlocks of the Great Old Ones.
6.) Mechs - These dwarves meld technology and magic into their beings. They're essentially arcane cyborgs - and in some ways are the Borg of my setting. They aspire for perfection of form and usually stay self contained, but send out missions to add new tools to their communities. They gain additional attunement slots (6), but when they attune, they attune for life as the magic is embedded into them. They also get to graft on mundane items and steal magic from other magic items in order to enchant something they've incorporated. While they keep to themselves most of the time, if they believe that a culture is worthy of contributing to their goals, they will attack, enslave, and then forcibly incorporate them into their culture. They are incapable of disobeying their Matriarch.
7.) Gyargants - They're size large and gain the abilities you'd get if the enlarge spell were permanent on you. They also gain the ability to throw improvised weapons as if they were light crossbow bolts that dealt 1d12+1d4 damage. They need larger mundane items, which cost more, but their larger weapons deal 1 larger sized dice damage. They can't cast spells of Divine, Arcane or Nature magic (meaning you're stuck with a fighter, barbarian or rogue usually - although they can be paladins that use the slots to smite).