If you want a multilingual site then don't create language specific values. Use generic values and have the display translate based off the viewing users language. For example your dropdown might have the below.
Value: COLOR_RED
Label: Red
Value: COLOR_BLUE
Label: Blue
COLOR_RED and COLOR_BLUE are what is stored in the database. Red and Blue are what is displayed to the user and is ran through translation API. So you can use language overrides to make them multilingual. It doesn't matter if this comes from a Query Select, Code Select, or regular Select field. As for example a Query Select you've the following parameters.
Value Column: this is Value as described above
Label Column: this is Label as described above
Using your custom database table above you'd have the below.
Code:
SELECT `iso_639-1`, `en_name`
FROM `#__comprofiler_languages`
Value Column: iso_639-1
Label Column: en_name
Now you'd just add language overrides for the values of en_name column. I guess you could still conditioning it as follows though.
Code:
SELECT `iso_639-1`, `[cb:if language_code="de"]de_name[cb:else]en_name[/cb:else][/cb:if]` AS 'label'
FROM `#__comprofiler_languages`
Value Column: iso_639-1
Label Column: label