For the purpose of this thread, foreign language =not English.
Several celebrities have been in the media speaking languages others than English. I sometimes wonder, how are their accents. I really don’t want to trust the comments below.
Some examples where I would love to know.
How are these accents? Feel free to add more.
Not a native speaker of any of these but: the former went to a French high school. She often dubs herself, so must be doing something right. The other was born in Israel, and probably goes back often enough.
And of course, it depends on what the native accents are. French is much more uniform than Italian, which has a bunch of accents.
Sure, but how do try sound to native speakers? BTW, from Portmans wiki bio, she left Israel when she was like 2.
She has a slight accent. But her Hebrew is very good. Although she does say she can’t read it well.
BTW here is Mila Kunis speaking Russian: Mila Kunis Speaking Russian in Moscow - YouTube
Speaks kinda like my brother speaks Russian 
He also came here at 10 (she came at 7). Has an accent and of course the vocabulary is not great.
Do you mean he has an American accent when he speaks Russian again? Because to me Kunis does not have even a trace of an accent in her English. Which is pretty amazing considering, according to her, she learned English by watching The Price Is Right!
And is it just me, but seeing Sandra Bullock talk like that puts a whole new spin on her Nazi-wearing ex… 
Yes. His English has no accent.
At the age of 7. In my experience, judging by immigrants’ kids, if you learn a language by immersion before 15 or so, you won’t have an accent.
Jodie Foster does not have an accent when she speaks French, at least not a foreign sounding one. Her speech is perfectly natural.
You didn’t ask, but Kristin Scott Thomas’ French is also indistinguishable from a native’s. She has played French characters in French movies.
Also, Steven Segal speaks Japanese. His pronunciation is not bad, though he wouldn’t be mistaken for a native speaker. I heard him do a long interview on television, and like many people who have learned Japanese outside a classroom, he has some difficulty breaking out of informal speech, and there are some wholes in his vocabulary, but overall he’s quite listenable. That is, he would be, if he had something worthwhile to say.
I saw some interview with him, describing his limited Italian he told of a New Years party at which he wished everybody a Happy Anus.
What do you mean by slight accent, is there a hint of Americanism in there (if that’s even a thing)?
Well an unhappy anus is something no one wants. 
His wife is Italian IIRC.
That’s fascinating, thanks.
Nobody would confuse Casey Affleck for a native, but his pronunciation is pretty good and he makes few grammatical mistakes. I’d put him at intermediate to high. In the interview he also sounds like he’s somewhat out of practice (I think he’d aaah and eeeh less often after a day or two of using his Spanish). The interviewer is from Spain and Casey points out that he’s used to Latin American accents (mainly Mexican ones, I guess) so understanding the interviewer is a bit harder for him; his own accent is still “anglo with good Spanish” rather than anything else.
That is “holes” BTW. I amused people in Japan by mixing ota-san with oka-san.
I can’t quite place the accent, maybe she’s just a bit too careful pronouncing the words. It’s not an American accent, that’s quite distinct in Hebrew. Americans just can’t do the "r"s and have no idea what a soft “l” is.
I’d call it an “unpracticed” accent - like someone who speaks a language well, but hasn’t spoken it for a while. Although there is a bit of American in there.
My cousins are like that, they speak Urdu and Punjabi perfectly, but due to being born and raised in the US, they rarely speak it. When they do speak, it’s formal, and a touch stilted.
Anybody knows how Bullock sounds like?
I don’t speak German at all, but Sandra Bullock’s mother is German, and Sandra has spent a fair bit of time in Germany. I’d be surprised if her German weren’t pretty solid, if not perfect.
sandra’s german is very good, with a slight bavarian accent as you’d expect with her mother being from Nuremburg.
my german friends all recognize her voice in english from her german language films which means she must do the voice over for them. (at least some of them)
Bah, I thought he was terrible! 
I was recently surprised to see that Gwyneth Paltrow speaks amazing Spanish: Entrevista Gwyneth Paltrow en Español sobre Película Contagion. - YouTube She is also doing that interview in Spanish via phone, which in my experience, is much more difficult than speaking face to face.
I heard she studied abroad in Spain as a teenager, but that is some incredibly good maintenance of a foreign language in that case.