There is no difference. They mean the same thing. In America, we are more likely to say "spoken English" or "spoken Chinese", etc. But oddly, we say "oral exam" or "English oral exam". In common speech (outside of the classroom), you will usually never hear anyone say "oral", because it has sexual connotations.

Oral English is a bad collocation. I'm a fraid native English speakers would not say 'oral English'. Spoken English is a pattern of English differing from written English. 'Oral' refers to a method in which people say something (opposite to the written mode).

yeah，oral English sounds weird

从表达的意思上，没有太大区别，都是强调language skills。从说的技巧上看，spoken English 更有技术含量。而oral English相对来说差一些,更多层面上侧重于口头上的表达