DebuggerSample.cs

using System.Net;
using Mono.Debugger.Soft;

using static System.Console;

static int PidToPort(int pid) => 56000 + (pid % 1000);

var pid = 49149; // process ID of the Unity Editor or the IL2CPP Game
var ip = IPAddress.Loopback; // IP where the Unity Editor/Game is running

var endPoint = new IPEndPoint(ip, PidToPort(pid));
var vm = VirtualMachineManager.Connect(endPoint);

var exceptionRequest = vm.CreateExceptionRequest(exc_type: null, caught: true, uncaught: true);
exceptionRequest.Enable();

var pumpSignal = true;

var eventPump = new Thread(() =>
{
    while (pumpSignal)
    {
        var eventSet = vm.GetNextEventSet();
        if (eventSet[0] is ExceptionEvent exceptionEvent)
        {
            WriteLine($"Exception: {exceptionEvent.Exception.Type.FullName}");
            WriteLine($"StackTrace:");

            foreach (var frame in exceptionEvent.Thread.GetFrames())
            {
                WriteLine(frame.Location);
            }

            vm.Resume();
        }
    }
});

eventPump.Start();

WriteLine("Press enter to quit");
ReadLine();

pumpSignal = false;
vm.Detach();

WriteLine("Bye now");

Compile against the Mono.Debugger.Soft.dll assembly that comes with your Mono installation. Unity ships with a local Mono installation.