Let's take a small step back.
Today a user can enforce a specific BV provider by setting it in the XML file. If not is selected, then Validation.buildDefaultValidatorFactory() pick one "randomly".
When booting BV programmatically, you can also specify which provider you want via Validation.byProvider(HibernateValidatorConfiguration.class).

A few remarks:

• if we want a qualifier, why not have a BV generic one @FromProvider(HibernateValidatorConfiguration.class). The only drawback I see is that this qualifier belongs in Bean Validation and that require us to depend on CDI which might be a no go after the discussions with the JavaFX team.
• I find it a bit annoying as a user when I define a provider in the XML descriptor but I also have to use a qualifier in my injection points.
• What happens for an existing BV 1.0 application today? AFAIK, injection of the "default" BV provider is done. I don't think we can break that behavior.