An acid stop bath is not desireable and not needed with staining and tanning developers ("pyro"). Acidic solutions can reduce the stain.

A plain water rinse is fine - and it arguably increases fixer life.

Some workers use an alkaline fixer as a one-shot immediately post development (they add fixer concentrate directly to the used developer - post development).

Post development I use a brief water rinse, followed by an alkaline fixer (TF-4).