How to add product from one store to another store in magento2?

Question

I have two store

• Store A -Store B

I have one configurable product SKU-test123.

Now I want to display it to StoreA's one CMS page for example: www.storeA.com/testcms (using catalog product widget)

Note:It's display perfectly.

When anybody click on the addtocart button it shoud be submit to the StoreB instead of StoreA.

Is there anyway to doing this?

I have try to replace from action of url from storeA to storeB but it's give me CORS header error.

Thanks for your help in advance.