My suspicion is that you are blocked because you demand perfection in every aspect from yourself? You should be able to achieve excellent writing in more technical areas, or in niche topics.
You will likely struggle to write poetically in English. Perhaps instead encourage skills that are not specific to English: good metaphors, writing simply and clearly, choosing an interesting topic.
I suggest you keep an eye out for compelling writing that is written by people that do not have English as a first language, and see if you can recognise their tricks. And remember: if you write then you are a writer. Just write. The best writers usually wish their writing were better, and can see all the flaws in their work.
You will likely struggle to write poetically in English. Perhaps instead encourage skills that are not specific to English: good metaphors, writing simply and clearly, choosing an interesting topic.
I suggest you keep an eye out for compelling writing that is written by people that do not have English as a first language, and see if you can recognise their tricks. And remember: if you write then you are a writer. Just write. The best writers usually wish their writing were better, and can see all the flaws in their work.