in/on/with/for

Before I chose a preposition, I would need the particular effort and the way it is phrased.

By effort, I mean something like a business or new adventure.

No, I want the actual word or phrase you mean—that will determine the preposition.

"I wish you all the best * your effort."

Effort = adventure/business.

Which one, 'adventure' or 'business'?

Can you not call a business an adventure?

Little GirlCan you not call a business an adventure?

Not at all. I suppose that you are thinking of the phrase 'business venture'.

I wish you all the best in/with your business venture.

Please see the fourth definition here:

http://www.thefreedictionary.com/adventure

ad·ven·ture

n.
4. A financial speculation or business venture.

[This is what I was trying to drive home earlier. Do not, please, give a straight "NO" when things are possible.

Little Girl Do not, please, give a straight "NO" when things are possible.]

It is still not possible. It is a meaning no longer generally employed. You cannot rely simply on a list of dictionary definitions. That is what many learners do when they compose very odd sentences. You need to become more familiar with how the language is actually used.

Y

In addition to being rarely used, it suggests a very risky or speculative business undertaking, which might not be what you wish to imply in your message.