Profile: BorisG4880

Problem:

How to change the custom field slugs and keep field values?

Solution:

You can change custom field slugs directly in within Types UI.

After change the field slug, all related custom field meta key will be changed automatically.

But I suggest you backup your database first in case any unexpected result.

Relevant Documentation:

Problem:

So I would like to create a block/view with that one and insert it the Elementor template.

Solution:

Toolset Blocks plugin is based on WordPress Blocks editor, it is not recommended to display View block into Elementor template.

In you case, I suggest you setup the view with classic editor, then display view's shortcode into Elementor template, for example:

https://toolset.com/forums/topic/creating-a-view-block-to-use-in-an-elementor-tab-widget/#post-2013245

Relevant Documentation:

https://toolset.com/documentation/user-guides/views-shortcodes/#wpv-view