There you can find a conversion to D&D 5e of the Voadkyn, a.k.a. Wood Giant.
Thin and Light. Voadkyns are smaller than other giants. They're 9 feet tall and weigh around 700 pounds and they have the physical proportions of humans.
Wood Elves Bonds. Voadkyns inhabit the same forests as wood elves. They have no lairs, choosing to live under the stars or with the wood elves for a while. The strong bond between wood elves and wood giants goes back further than either race can remember. This may account for Voadkyns' fey ancestry.
Solitary lives. Wood giants don't mix with other intelligent creatures but elves.
Humans who have had contact with Voadkyns describe them as friendly enough, but flightly and frivolous, never in great hurry to do anything other than eat and drink large amounts of wine. They don't fight unless forced to defend themselves or their allies.
Treasure Lovers. Voadkyns are fond of finely cut gems and magical items. Sometimes they join an adventurers' party in disguise, just to steal gems, jewels or magical treasure.
WOOD GIANT (Voadkyn)
Large giant, chaotic good (neutral)
Armor Class 15 ( studded leather armor)
Hit Points 67 (7d10+28)
Speed 35 ft.
STR 20 (+5) DEX 16 (+3) CON 18 (+4) INT 14 (+2) WIS 12 (+1) CHA 10 (+0)
Saving Throws Dex +7
Skills Perception +5, Stealth +7
Senses darkvision 90 ft., passive Perception 15
Languages Giant, Sylvan
Challenge 4 (1,100 XP)
Fey Ancestry. The wood giant has advantage on saving throws against being charmed and magic can't put it to sleep.
Low Cunning. The wood giant can take the Hide action as a bonus action on each of its turns.
Mask of the Wild. The wood giant can attempt to hide even when it's only light obscured by foliage, heavy rain, falling snow, mist, and other natural phenomena.
One with the Woods. When in an area heavily obscured by foliage, the wood giant can use its action to become invisible until it moves or takes an action or reaction.
Plant Camouflage. The wood giant has advantage on Dex (Stealth) checks when it's in a wood or forest.
Shapechanger. The wood giant can use its action to polymorph into a humanoid of medium or small size, or back into its true form. Its statistics are the same in each form. Any equipment it's wearing or carrying isn't trasformed. It reverts to its true form if it dies.
Multiattack. The wood giant makes two greatsword attacks or two longbow attacks.
Greatsword. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 16 (3d6+5) slashing damage.
Longbow. Ranged Weapon Attack: +7 to hit, range 225/900 ft., one target. Hit: 12 (2d8+3) piercing damage.