Under QQE, the main operating target for money market operations is the monetary base, and various assets (with JGB purchases being the main operational tool) are purchased under the target.
As the third difference, while forward guidance in the Federal Reserve, the BOJ, and the BOE is commonly regarded as “state-contingent” or “threshold-based,” both the Federal Reserve and the BOE include employment-related thresholds, unlike Japan. The Federal Reserve has a dual mandate of promoting price stability and maximum employment, so the reason for this is clear.