Deploy Qt5 application: always create a qt.conf file at the same folder of application. The content of qt.conf is something like below:
[Paths]
Prefix=../lib/Qt
Libraries=lib
Plugins=plugins
Imports=imports
Qml2Imports=qml
Prefix: gives the path of Qt library. It can be relative path Libraries: path to core of Qt library. It will be constructed as: Prefix/Libraries and so on.