Good to know. Can you give more hints on how you achieved that? Did you use Assembly.LoadFrom or another method?

This can be useful for people who will encounter the same issue.

In my case I'm still using DllImport:

[DllImport(<dependent dll>)]
private static extern bool SomeFunction();

[DllImport(<my dll>)]
private static extern bool SomeOtherFunction();

Both Dll's are placed in Assets/Plugins and I make sure so call SomeFunction first before calling anything from my own plugin.

I did not think about using Assembly.LoadFrom. That may be a better idea...

I'm not an expert with loading external resources. But it seams that DllImport is a generic method to load unmanaged code (from any DLL), whereas Assembly.LoadFrom only works with CLI-managed code (that could also be embedded inside a DLL).