You speak a language, you don't speak an ‘accent’:
“Jorge is from Barcelona, he speaks Spanish and English. Although his English is very good, he speaks it with a strong Spanish accent”.
From Longman Dictionary
have an accent
- The man had a Spanish accent.
speak with an accent
- She spoke with an accent that I couldn’t understand.
a strong/broad/thick/pronounced accent (=very noticeable)
- She spoke with a strong Scottish accent.
- a broad Australian accent
an upper-class/middle-class/working-class accent
- Sebastian spoke with an upper-class accent.
You can also say “speak in a(n) adjective (language)”
From YouTube, a tutorial entitled: How To Speak In An American Accent
Funnily enough, the presenter is British and has a posh English accent.