Welcome to the forum.  Have fun with the game. 

Happy birthday Bumbleguppy.   

20th birthday today!  Long live TQ.   

Kerplunk and Prosoro will be live streaming the game today from 9am EDT, 2pm BST, 3pm CEST.

https://www.youtube.com/@kerplunk-gaming

https://www.twitch.tv/kerplunkgaming

Another interview Arthur's just done.

Face (Your) Nemesis: Titan Quest II Chapter 4 Throws You Against a Goddess
 
The journey of your hero toward immortality continues. With Chapter 4, Titan Quest II expands its world once more, leading you into the untamed Wild Lands.

There, your destiny unfolds on multiple fronts: bring the conflict with the centaurs to its decisive end by confronting King Centaurus, and steel yourself for the inevitable clash with Nemesis herself. The goddess has long lingered in the shadows, carefully plotting her next move — and now, your path draws you deep into the heart of one of her vast temples.

Prepare yourself. What lies ahead will be your greatest trial yet.

The next Early Access update for Titan Quest II is coming soon — and it will be the largest and most epic chapter to date.

Check out the new Teaser on YouTube:

Verify the game files and make sure all your drivers are up to date.

If that doesn't help then try uninstalling and re-installing the game.

I think you need to use LAN like Radwin or similar to trade with others.  Then ingame you drop the item and the other player picks it up.