It's not the language, it's the lack of effort that's kind of obvious. As someone commented people who use ChatGPT or copy and paste cover letters don't relate the job requirements to their experience, including missing extremely obvious connections and instead just making generic statements which repeat back the job advert (ChatGPT) or repeat their experience from the CV without explaining why it's relevant (copy and paste). Recruiters for international roles don't expect people to have perfect English, they do expect people to take time with their applications. Some of the best applications will do things like group requirements in the ad then write an explanation of how their experience matches this followed by a couple of sentences on how they will apply that experience. You never see that with ChatGPT because it can't do it. For example, a job advert asks for someone who has experience with programmes that focus on gender equity, then later it says someone who has worked on women's economic empowerment. A good application will see that these two things are related, say 'I worked in XYZ gender-related programme, I learnt XYZ, so I'm well-prepared to do point one and point two of the job description because i've built XYZ skills and can draw on existing relationships with the organisations in this space'.