Buying something like a Labubu doll is generally not a religious issue by itself. The main thing to consider in Islam is whether an object is being used for worship, belief, or promoting a religious idea.
Many toys, characters, or fictional figures come from mythology, folklore, or fantasy stories. But when people buy them today, they usually treat them simply as toys, collectibles, or decoration, not as something connected to belief or religion.
So if someone buys a Labubu doll just because it is cute or trendy, and they do not believe in or promote the mythology behind it, then it would generally be considered permissible.
However, if a person feels that the character’s background or story promotes ideas that make them uncomfortable or conflict with their beliefs, they can simply choose to avoid it. Islam often allows such things but leaves room for personal discretion and awareness. What matters is belief and intention, not merely the fictional origin of a character.