Pure ethanol freezes at -173 C. Everclear is closer to -50 C. You’ll definitely need dry ice to freeze it unless you have an industrial deep freezer.
Edit: i reread your comment and the op. Op isn’t saying freeze the ethanol solid. They’re saying put the ethanol in the freezer with the basil so that they both cool down. The ethanol will remain liquid but be colder. You get a better extraction with fewer contaminants that way.