Definition
Multilingual SEO is the practice of optimizing content for multiple languages and regions. Multilingual AEO is the same applied to AI engines. The opportunity: most AEO tools (Profound, AthenaHQ, Peec) only score English. Hindi, Spanish, Portuguese, Arabic, Indonesian markets have ~3 billion potential users but near-zero AEO tooling. First-mover advantage is real.
An Indian D2C brand selling in Hindi + English. English content is over-indexed in tools; Hindi content has no AEO scoring available, yet ChatGPT/Claude/Gemini all answer Hindi queries.
How to optimize
Use hreflang. Translate (don't auto-translate) key pages. Optimize for local entity signals (Wikipedia in target language, local press). Track citations across languages separately.