I suppose by "without accent" you mean "with General American accent"? German or French can be spoken without accent, but English doesn't have one universally agreed "standard accent". What's without accent to the American is just an American accent to everyone else.
This isn't completely true: even within America, there's different accents. So people with a "standard American accent" (generally midwestern) listen to Southerners talk and say they have an accent. There's also northeastern accents (such as the famous Boston accent).
Of course, these days, a lot of the accents are disappearing because of mass communications, so the "American accent" is homogenizing, but those other accents aren't completely gone yet.
The word "accent" implies that it is being compared to some kind of reference. You might be looking for the word "dialect" here.
For example, if you have two speakers with English as a first language and a third from Germany with English as a second language, the native English speakers will probably detect a German accent in the ESL-speaker's dialect.
People get into long internet arguments over this, but the closest thing to a neutral English dialect is General American English, also sometimes called Broadcast English because newscasters, TV personalities, and actors would be trained this dialect so as to not sound like they are "from" anywhere in particular. It used to be common as well for highly-educated or upper-class individuals to hire speech coaches to teach them this dialect in order to "lose their accent". It still may be common for all I know, but I believe the deliberate acquisition of General American is probably on the decline.
