Using https://wordpress.org/plugins/lj-xp/ I was able to do so not only for some individual entries (it auto cross posted categories too) but also for a bulk of my earliest entries (from back in 2017). However, the 2018 ones and 2019 ones didn’t get cross-posted. I got a timeout with Nginx 500. This was when I clicked on some Update options and cross post all older entries in the settings.
Great tool/plugin. Much appreciation to Stephanie Leary, and the other names involved in the project for their time and effort!