Yes, according to some Islamic scholars, seahorse is considered halal (permissible) to eat.
Based on the reference provided, the reasoning behind this permissibility stems from the general Islamic principle that all aquatic animals from the sea are halal. Imam ShaiE confirmed this stance. This understanding is based on interpretations of Islamic texts that broadly permit consumption of sea creatures.
Therefore, while individual interpretations and rulings may vary, a common view holds that seahorse consumption is halal within Islamic dietary guidelines.