Klaviyo Pop-up

You should be able to trigger Klaviyo popups using a Run Javascript action in Replo:

https://developers.klaviyo.com/en/docs/how_to_custom_trigger_a_popup_or_flyout_form has the javascript snippet to run, and

https://support.replo.app/articles/1713116416-interactions#run-javascript has documentation on how to use the Run Javascript action for this!