You can delete a comment by meta key or meta values.
1) Meta fields: You can delete a comment by only meta key. if you want to delete comment meta key and its value so also you can do it easily using this plugin.
2) Date Interval: You can delete a comment meta using the 3 option in the delete comment meta date interval.
=> Older than: You can delete comment meta that are older than your selected days
=> Created within last: You can delete comment meta that are created within last your selected days
=> Created between : If you want to delete a comment meta between the start date and the end date. Then this option will be helpful for you
3) Detele Time: WP Bulk delete Pro provides functionality to scheduled delete at a particular time. and You can choose the scheduled at option at Delete Time to scheduled delete. it has 2 options.
Delete now => It will start delete operation just after you press the delete button.
Schedule Delete => If you want to run delete operation later at particular time. You can also repeat delete operation Once Hourly, Once Month, Once-Weekly, Twice Daily, Once Daily. You can see repitative scheduled deletes at WP Bulk Delete>Schedule Delete page