Why do you think you need a smart rule? A smart rule is intended for habitual processes. See this blog post on how to determine what suits your needs…
That being said, your inquiry is no more complicated than this Tools > Batch Process on selected items, using the Name Without Date placeholder…
You’re welcome
Please read the linked blog post to help understand how to choose an automation option. Bear in mind, there are no mandates there but some options may be more appropriate in certain situations.