Untranslated value not showing in entity reference editing for multilanguage site

Problem/Motivation

In a multilanguage site with a translatable entity reference (to taxonomy term for example) field in a paragraph type, where the "hide non translatable fields" is checked for the paragraph type, translating the paragraph does not pre-fill the entity reference field with untraslated value.

Steps to reproduce

Create a paragraph type with an entity reference field pointing to a taxonomy vocabulary.
Set the field as translatable (I know usually entity reference fields are not translatable).
Set the paragraph type as translatable and enable "hide non translatable fields".
In default language, create a paragraph instance and set the reference field to point to a taxonomy term.
Translate the paragraph instance: you should see the reference field pre-filled to point to the taxonomy term, while it is empty (tried with select, radio and autocomplete widget).

Proposed resolution

Retrieve untranslated pointer value.

Remaining tasks

Test.

User interface changes

?

API changes

No.

Data model changes

No