@Jordius Thank you for your question about non-English endorsement submissions.
Generally speaking, applications should be submitted in English along with English language resumes and work history. Supporting documents can be submitted in native tongue, however. Regardless of what you submit, our Member Services Specialists will work with you to ensure they understand the contents of your documentation so that the endorsement process is easy and efficient for you.
Manager, Member Services
For questions or issues related to candidate/member services, please contact: https://www.isc2.org/Contact-Us.