Is there any possibility to clone the app ? I mean make double app in one user (not clone via users)
Clone the app
anyname99 not possible yet, no. AOSP might get this feature in the future.
"Clone profile: Android supports the creation of a separate clone profile user type to enable running two instances of a single app on the device. AOSP doesn't provide end-to-end support for the feature. OEMs need to add customizations to deliver the complete feature to Android users." Source.
So technically it exists in AOSP, but it's not an end-to-end implementation.