Is this your great business idea? No, it is simply not possible from those pictures. No one will be able to do that. Nor want. You need to have these devices in your hands if you are serious about copying them. Plus they are programmable, so you need more then just circuit diagram. In fact, it might be easier to just design it from scratch then to make an exact copy.
No, this is not a business idea, I'm not interested in making and selling them, I want to make it free for everyone, because everything has been built on one or other stolen things.
No. 
If you want to know how its made then you either need to buy it and reverse engineer it yourself. Or find schematics online either from the source of the product or the person who created it initially if they are happy to provide the schematics.
There are many issues. Mainly we cant read chip markings from those photos, if there is software we cant guess how its programmed.
Either of them are not possible. Why do you think I posted here?
Sorry, not possible. The markings on the chips are not visible. But there are many tutorials on such audio transmitters and receivers. You can study those.
Thanks but most of them are bigger and they are not remote controlled.
Nice handle. Talk to one of your H1B ripoff artists here in the states, maybe they can help. Should be able to steal all you need. Or see if China has already stolen it and making knockoffs for about 50 cents each.
I don't care about H1B visa holders from India, and it is the US and the western world which has stolen from India for many centuries, because of which the west is rich and technologically advanced. I searched for similar things on Alibaba and Ebay and they are not sold, but if it takes less than 50 cents to make, the seller is engaging in day light robbery by charging 190 euros for them. You have Iceland's flag and you are insulted as if you are from US, are you ashamed of being from USA?
And where are the results of your own actual attempts to do that?
I don't know electronics, so I cannot attempt reverse engineering it.
Here is a link to something similar
https://www.hobby-hour.com/electronics/wireless_microphone.php
Thanks for this, I want to make something small.