This is howto Find & Replace Web.archive.org links with Date fields;
Make sure to use Updraft to backup DB before you start!!!!! If something goes wrong, you can quickly restore without much effort.
use the “Search Regex” WordPress plugin
(make sure to check the regex box on the right side)
for the Replace field, on the right side, choose “REMOVE”
You can then click the Search button to see how many are there, and then click the “replace all” button to replace all instances of web.archive.org urls in your posts.