Below is just cherry-picked search results, selected largely by whether last few lines in the abstracts support my narrative, but I mean, it's a problem obvious enough that the rest of the world just knows.
0: "Not All Languages Are Created Equal in LLMs: Improving Multilingual Capability by Cross-Lingual-Thought Prompting": https://arxiv.org/abs/2305.07004
1: "Better to Ask in English: Cross-Lingual Evaluation of Large Language Models for Healthcare Queries", https://arxiv.org/abs/2310.13132
2: "Do Moral Judgment and Reasoning Capability of LLMs Change with Language? A Study using the Multilingual Defining Issues Test": https://arxiv.org/abs/2402.02135
3: "Should We Respect LLMs? A Cross-Lingual Study on the Influence of Prompt Politeness on LLM Performance": https://arxiv.org/abs/2402.14531
4: "Exploring Multilingual Human Value Concepts in Large Language Models: Is Value Alignment Consistent, Transferable and Controllable across Languages?": https://arxiv.org/abs/2402.18120
5: "How do Large Language Models Handle Multilingualism?": https://arxiv.org/abs/2402.18815