If we access https://docs.python.org/3.8/library/asyncio-queue.html#asyncio.Queue
we can see the text

Make Deprecated since version 3.8, will be removed in version 3.10

is perfectly visible in english. However if we change the language to pt-br by using the link https://docs.python.org/pt-br/3.8/library/asyncio-queue.html#asyncio.Queue

We can see that the whole page is in brazilian portuguese, except that text, and we are not able to translate it in anyway that is visible in the page. What should we do in CPython so we can translate this string?

This tracker is for patching the english Python docs and CPython interpreter.  Questions about using python should be asked elsewhere.

The translated docs are the responsibility of a separate translation team and specific language teams.  Either they chose not to translate that sentence, or it was added after their last translation update.  see
https://devguide.python.org/documenting/#translating

I checked and the directive was indeed made translatable in #32087

So like Terry said, this should be brought to the attention of the PT translation team.  The strings seem to be translated (https://github.com/python/python-docs-pt-br/blob/3.10/sphinx.po#L46), so there’s something else going on (even in the current 3.10 docs).