You would have to recreate your package in .net 4.6 because it’s not forward compatibile.
However,
Could you try creating your project in Windows compatibility?
This compatibility mode is using .net6 or .5 I always forgets which. It may run according to this artice: Version compatibility in .NET Framework - .NET Framework | Microsoft Learn
.Net is backward compatible. However in UiPath packages from 4.6 are not woring on Windows compatibility so you should try first.
I just saw this but the answer above is not fully accurate.
The framework for windows legacy is fixed at 4.6. Your addin is not supported due to this as the language version is too high.
The next compatibility option is Windows, this is using .net core and 64 bit compatibility.
The min is 5.0
So your code sadly falls outside of scope for either compatibility.
Considering the 4.6 projects are being phased out I’d recommend updating your package to one supported by the Windows Compatibility.