JS+ CKEditor plugins themselves can be installed to any CMS or framework you want. But for Drupal 8 all the add-ons need to be wrapped with Durpal compatible module.
We've prepared such modules. They will help you manage JS+ CKEditor add-ons inside CKEditor: to add/remove new plugins buttons to toolbar and change all the options using UI in the administrator panel.
If you are on purchase step, please choose CKEditor edition of the add-ons. Drupal modules are available on this page for free and will work fine in pair with CKEditor plugins.