I can't see the button to share a file with Direct WiFi, even if my phone is connected to an other device.
So how to use this feature ?
Direct wifi file sharing is a very limited feature on pure Android. You can use it to DLNA media sharing but it's far from Samsung's Wi-Fi direct implementation which allows to send or receive files seamlessly. Unless Asus will do something comparable, there is no easy way to fast file transfer. As an alternative, you could use FTP transfer via local network. It won't give that good results but at least it will work on everything.
I use the app Syncthings, which syncs whole folders, not individual files.
After you get it set up between two devices, it works automatically, if you want that.
Syncthings can sync over WiFi or mobile data.
It is available on Windows & Mac also.
Thanks for your replies !,
In fact, I try to find a good way to transfer pictures without any compression and without a computer or an external storage between 2 phones. I used to use the NFC transfer but it is not very fast ...
ASUS had ShareLink before ...
You could try some 3rd party wifi direct app on both phones. Make sure both phones have wifi and location activated or it won't work