Posts do not need to be in English. In fact, it's best to write in the language you are most familiar with. There are tags for various foreign language posts.

kr - Korean
cn - Chinese
fr - French
de - German
es - Spanish
jp - Japanese

Running a witness requires a dedicated system with a high bandwidth connection, 24+ GB Ram (GPU Ram counts toward this total), and significant available hard disk space (250 GB SSD and 1+TB HDD minimum).