What are the chances if I'm new to the screenplay business to sell a horror film for at least $400k with a very original concept through agents one American and the other British because I won't talk to producers/Sony/Columbia films by myself what is important to them  its general idea/how it was written in terms of format

What exactly are you asking? Is it possible? Of course.
If your idea is big enough and catches the attention of the big guys, bidding wars can result. Usually done through Agents or representation.

I don't understand the last bit about 'general idea' and format. Maybe you can elaborate.

If you're saying somebody official at Sony Columbia has already expressed an interest and right now you have two established agents negotiating on your behalf, then the answer is maybe.

If you're just asking hypothetically, or in a general sense, then the answer is far less positive. Do you have a completed screenplay? Has Sony or an agent read it, or even a synopsis, outline, treatment, even a pitch?