Does MySQL 5.5 support shared database with separate schema?
My understandng of MySQL is that what they call a "database" is a schema on other db's.  So the answer to your question is "yes" or "no" depending on the specifics you are asking.  In fact "create schema" just maps to "create database" on MySQL.

So yes, you can do one schema per tenant but that is not any different on MySQL than one database per tenant.  So not sure if that is a yes or no.