A kobold is a mythical sprite. Having spread into Europe with various spellings including "goblin" and "hobgoblin", and later taking root and stemming from Germanic mythology, the concept survived into modern times in German folklore.
Kobold
Drawing of a Kobold
The Heinzelmännchen of Cologne left the city after a woman tried to see them by tripping them with peas strewn on the stairs.
Heinzelmann was a kobold who haunted Hudemühlen Castle.
A goblin is a small, grotesque, monstrous creature that appears in the folklore of multiple European cultures. First attested in stories from the Middle Ages, they are ascribed conflicting abilities, temperaments, and appearances depending on the story and country of origin, ranging from mischievous household spirits to malicious, bestial thieves. They often have magical abilities similar to a fairy or demon, such as the ability to shapeshift.
The Princess and the Goblin by George MacDonald, illustrated by Jessie Willcox Smith, 1920