English Translation
I mentioned your name to him.
The presence of “gegenüber” in this sentence is incomprehensible to a non native German speaker. The propensity of the German language to always want to state the obvious is laughable!
I mentioned your name to him.
The presence of “gegenüber” in this sentence is incomprehensible to a non native German speaker. The propensity of the German language to always want to state the obvious is laughable!
“gegenüber” corresponds to the “to” in the english sentence. Or you could say “towards”.
Without it, it would sound funny as it would change the meaning.
If it was just “Ich habe ihm deinen Namen erwähnt”, it sounds like mentioning the name was a kind of favor for “him”. I think “I mentioned him your name” would sound just as funny.
I actually don’t know how to say it without “gegenüber”. “erwähnen” is closely linked to “gegenüber” when it comes to expressing the “to whom” part.
And other prepositions such as “zu” or “für” don’t work here.
On wiktionary: gegenüber - Wiktionary, the free dictionary you can see the “to/towards” meaning in #2 and #4.
Like @pitti42 says, you can best translate “gegenüber” in this context with “towards”.