What is the IEEE style for a translated quotation?
IEEE is based on the Chicago Style, so whenever you do not find any guidance directly from the IEEE, it is best to consult the Chicago Style Manual. In Chapter 11 of the Chicao Style Manual, titled &quot;Quotations and Dialogue&quot;, you can find some relevant directives. For instance:

First, make sure your audience really needs a translation from
English sources; if you audience is an academic one consisting of
researchers who perhaps publish themselves in international journals,
then I am not sure whether translations are really necessary:
'Whether to provide translations of quoted passages depends on the
linguistic abilities of the likely readers' (11.86).

Second, you can simply quote the sentence in your translated version (in the usual form you use to quote another source), but consider putting the original text into a note
(11.88): 'In many works, quotations from a foreign-language source
need appear only in translation. Should the original be necessary, it
can be placed in a note.'

Third, credit the translation to a published source of the
translation with all bibliographical details. If such a source does
not exist, then the Chicago Manual (11.89) states: 'Authors providing
their own translations should so state, in parentheses following the
translation, in a note, or in the prefatory material—for example, “My
translation” or “Unless otherwise noted, all translations are my
own.”'