(See the best response by Multiverse7.)
Is there anyway to initiate a window between two clients for trading items/obj, Iíve tried a few concepts but I keep running into dead-ends using skins. Iíve also tried searching byond topics through google and have found nothing so forgive me if there is an existing discussion on this. Thanks for reading! 🙏🏽
Best response
If you are having trouble initiating the trade itself, a simple way is to override client/Topic() and send the target player a topic link containing the ref text for both clients, so that if they click it and accept the trade, the info can be sent to a trade proc, so that it has access to all of the relevant information.

As for the interfaces themselves, that depends largely on how you choose to design them, but it might be similar to the interface of a card game, where each player sees what they are offering on the bottom half of the screen, and what the other player is offering on the top. Basically, you need to display 2 extra inventories where the one on the bottom is populated by that player, while the one on the top is just displaying what the other player is inputting. Obviously, this will need to interact with the player's existing inventory to work. If you are struggling with interfaces, you will have to be more specific and explain what you are having trouble with.
I made a simple a skin window with two grids and two accept/decline buttons. So maybe I can implement your suggestion? I just wasnít sure how to go about referencing the clients and have them interact with a trade window. Thanks so much for your quick response! Are there any card games that you can reference that would serve as a good example?
In response to Mikeche
I'm glad I could help. Since you are using grids to display items, I don't think a card game will be of much help. Almost any card game in BYOND is going to use screen objects, objects on the map, or even HTML elements in a browser control. If you must see an example of this, you can take a look at The Magic Man's Manacept game. The developer has provided the source code on that page, but you must agree to some very strict terms.

I never liked BYOND's grids. I always found them buggy, and there's only so much that you can do with them. I think the virtually unlimited potential that map and browser controls provide is much more appealing, but if grids work for you then that's fine.