Tested the issue on Windows 10, Ubuntu 14.04, Mac OS 10.11.6 using chrome reported version #54.0.2840.14 and latest canary #55.0.2854.2. 
Observed that the issue is not reproducible.

Attaching screencast for the same.

Following are the steps followed to reproduce the issue.
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1. Changed the language and input settings by selecting Portuguese(Brazil) from system level and then restarted the system to make changes effective.
2. Changed the language and input settings in the chrome browser and restarted it.
3. Launched the browser and selected translate language on one of the english site i.e https://en.wikipedia.org/wiki/Main_Page and one chinese site i.e http://home.sina.com/
4. Observed that the language translation happened to Portuguese(Brazil) as expected.

Reporter@ - Could you please let us know on which particular site you are facing the issue and check if your system has language package installed on it.

Deleted: 644801.ogv 10.9 MB

	644801.ogv 10.9 MB View Download

The same problem persists in 55.0.2868.3 version dev version (64-bit), even having already wiped all the data and reset the settings.

Deleted: google.ogg 30.8 MB

google.ogg 30.8 MB Download

Retested the issue on Ubuntu 14.04 using reported version #55.0.2868.3 as per the comment #0.
Observed that the issue is not reproducible.

Attaching screencast for the same.

matheusvigo23@ - Could you please check this issue by creating a new profile without any apps and extensions and please let us know if the issue still persist or not.

Deleted: 644801.ogv 15.6 MB

644801.ogv 15.6 MB Download

I cleaned all the files and delete my profile and your data, extensions and the problem continues.

Deleted: google.ogg 20.1 MB

google.ogg 20.1 MB Download

This issue looks similar to bug id: 651253.

Hence, marking it as duplicate and merging into  issue 651253 .