Is there a standardised guide to do it?
ICD-10 and EFO are not easily compatible, but there are numerous examples of conversion tables, e.g., this repository: EBISPOT/EFO-UKB-mappings. However, it covers a small fraction of phenotypes. Other option is UK biobank tables, but these are so weird with ICD-10 codes, which are mixed with other systems e.g. https://pan.ukbb.broadinstitute.org/docs/per-phenotype-files/index.html
So is there a right way to do it for all icd-10 codes? Nor UK biobank nor EFO websites provide some answers.