Cisgender Unicorns and Transgender Ducks
No, you can't CD without being TG. Cisgender people don't crossdress. Cisgender people
don't dress themselves in a manner that is commonly associated with the opposite gender. Crossdressing is by definition a transgender behavior regardless of personal intent.
People who crossdress and still claim to be cisgender are lying about themselves and lying about what it means to be cisgender. Cisgender crossdressers are fantasy figures, like unicorns. In reality, every crossdresser is a queer transgender duck. You can protest with a quack and waddle for cover, but no one (except you) will mistake you for anything else.