What did the court decide in Indiana v. Edwards?
Answered for: US
the Constitution permits States to insist upon representation by counsel for those competent enough to stand trial under Dusky but who still suffer from severe mental illness to the point where they are not competent to conduct trial proceedings by themselves
The Court held that a state may require counsel for a defendant competent to stand trial but not competent to conduct the trial personally.
This answer is true in US and nowhere else on this site. Another jurisdiction is another answer, or an honest gap: see what has been read for US.