Submitting a paper to a journal: is it OK to indicate the Editor of that journal as a reviewer?
In the journal where I am an associate editor, there is an unofficial policy that editors do not review.  The reason for this is simple and pragmatic: if somebody is an editor, they are doing a whole bunch of work of the journal in that capacity.  Asking them to review as well is double-duty, and the journal wants to spread the service load more broadly over the community.

Now, there are special cases where an editor will do a review, particularly when there is difficulty obtaining a sufficient number of qualified reviewers.  In my experience, though, this is rarely due to difficulty finding people with sufficient knowledge to review, even in highly specialized fields.  Instead, it is most likely to happen with a certain species of dreary borderline paper that is very badly presented but possibly salvageable---confronted with such a beast, reviewers suddenly all become "too busy at the present time" and an editor may end up having to review it themselves.

So, returning to your question: I would suggest not bothering to suggest an editor as a reviewer.  If you have a choice to suggest a handling editor, that's fine, but your suggestion of editor as reviewer is likely to be simply ignored.