Is it possible to package a sketch with dependent libraries for cross-platform compatibility?
I would suggest switching to UECIDE instead of the Arduino IDE. (Yes, shameless plug, it's my IDE).

UECIDE has a facility that I dubbed "localizing" a library whereby it copies it into a libraries folder within the sketch folder itself, and that copy of the library is used in preference to any other library named the same in the system.

That means that a sketch and its libraries then become completely self contained in one folder, and it's perfectly possible to have different versions of the same library in different sketches.