There is no need for that, as KDE Plasma already comes with its own Global Menu widget, which does the same thing.
Well, the items shown in the menu under the application title ─ which for KDE Plasma is a separate package called
plasma5-applets-window-title, available from the AUR ─ are already shown under File in the Global Menu.
plasma5-applets-window-title widget does have (a little) more functionality than meets the eye, though. When double-clicked, it maximizes or unmaximizes the window.
I myself use the
plasma5-applets-window-title applet in combination with the
plasma5-applets-window-buttons applet ─ also from the AUR ─ which allows the window buttons to appear in the top panel when the window is maximized, and for the window title bar to be omitted in that case.
I'm afraid that at this point in time, there is no way of getting what you want it to do ─ or at least, not from any package in the repo or in the AUR. You might look around at store.kde.org for something that does what you want, but I doubt that you'd find it ─ I've been looking around quite a lot on there myself for interesting Plasma applets, and I haven't come across that yet.
You have to keep in mind that KDE Plasma and XFCE are two entirely different environments. Plasma is based upon the Qt widget toolkit, while XFCE is based upon the GTK widget toolkit, and they are very different in nature.