The service "media_library_importer.service" has a dependency on a non-existent service "queue_ui.batch".

Version 2.0.2 had the dependencies list as:
dependencies:
- drupal:media
- drupal:media_library
- queue_ui:queue_ui
Where your patch is:
- drupal:media
- drupal:media_library
- drupal:queue_ui

Since version 2.0.x, the media_library_importer depends from the queue_ui contrib module → .

Thus, make sure to clean require it through composer (that is the recommended way to add drupal modules since Drupal 8+), with the suggested command:

composer require 'drupal/media_library_importer:^2.0'

or eventually manually add also the the queue_ui contrib module → in your code base.

Also make sure to enable it in your application manually from the Drupal backend (/admin/modules) if not already done.

All this will make the media_library_importer 2.0.x up and running correctly, fixing the following:

"The service "media_library_importer.service" has a dependency on a non-existent service "queue_ui.batch"

PS: @carlodimartino you are wrong, as the 'drupal' prefix is used to refer to drupal core modules.

The following:
- queue_ui:queue_ui

is the proper way to define dependency from the queue_ui contrib module.

Just adding the dependency to composer.json and the info.yml is not enough because that will not install it. And depending on the site manager to install it manually is no good practice, as if they don't know and forget it, that will break the site. The safe option is to install it via an update hook.

See MR !2 for the update hook.

thanks @mvonfrie ... more than welcome,
MR merged and new 2.0.4 just released.

Automatically closed - issue fixed for 2 weeks with no activity.