Here's some stats for a goblin assassin- mine are acting as spies for well-organized Hobgoblin mercenary company that is working for the main antagonist in my game, but they could easily be slotted in as Dhakaani goblins for a Eberron campaign.
Goblin Assassin (Rogue 3)
Medium Humanoid, Neutral Evil
Armor Class: 13 (leather)
Hit Points: 15 (3d8)
Speed: 30 ft.
Str 8 (-1) Dex 15 (+2) Con 10 (0) Int 10 (0) Wis 16 (+3) Cha 7 (-2)
Saving Throws: Dex +4, Int +2
Skills: Stealth +6, Perception +5, Acrobatics +4, Investigation +3, Athletics +3, Sleight of Hand +4
Senses: Darkvision 60 ft., passive Perception 15
Languages: Common, Goblin, Thieves Cant
Sneak Attack +2d6 damage 1/round against targets the Goblin has advantage against
Cunning Action: The goblin can take the Hide, Dash, or Disengage action as a bonus action on each of its turns.
Assassinate: The goblin has advantage on any creature that has not yet taken an action in combat. In addition, hits against surprised targets are automatically critical hits.
Poison: Many goblin assassins use poison, particularly on their darts (which are often used to cover an escape). Carrion Crawler Mucus (DMG), Serpent Venom (DMG), and Basic Poison (PHB) are all common.
Dagger: Melee or Ranged Weapon Attack, +4 to hit, reach 5 ft., range: 20/60, one target. Hit: 1d4+2 Piercing damage.
Darts (5): Ranged Weapon Attack, +4 to hit, Range 20/60, one target. Hit: 1d4+2 Piercing damage + poison (see below)
Description: While Goblins are not known for being particularly well-focused on any particular task, their natural small size, natural stealth, and basic self-centered ruthlessness can make then useful spies on assassins for a leader who has sufficient strength of will and arms to keep them in line and compel them to stay focused on their mission. Goblin assassins are much more grim and focused than the average Goblin, keen observers who prize their own survival and always have an eye out for potential targets or ambushes. Goblin assassins prefer to strike when their target is totally helpless, infiltrating towns or camps under cover of darkness and having no qualms about killing sleeping victims. Their equipment depends on their mission, but often includes poisons and caltrops that are used to cover their escape in the event that they are discovered or interrupted.