Short answer: test the language you actually publish in. The best tool for English sales copy may not be the best for Spanish support emails, Arabic summaries, or French legal-style prose.
A repeatable language test
- Write one source brief in your native language.
- Ask ChatGPT, Claude, Gemini, and Perplexity for the same output.
- Have a fluent human mark tone, accuracy, idioms, formality, and hallucinated facts.
- Count edits required to publish.
What to watch for
- Overly literal translations
- Wrong level of formality
- Invented local facts, laws, or prices
- Region mismatch: Latin America vs Spain, Canadian French vs France, etc.
Use the Compare Shortlist and scorecard to record the winner for your language and workflow.