I was wondering if you can implement what this mod does. I would have updated this mod myself if I knew java.
InventoryHotswap Mod for Fabric

There are currently two separate swapping features in Tweakeroo: Hotbar Swap and Hotbar Scroll. Enable them in Tweaks and then look in Hotkeys for the usage keys.

As an example, for Hotbar Scoll I have hotbarScroll bound to Q, so then I can hold Q to see the overlay, and scroll with the mouse to select which inventory row I want to swap with. A quick tap of Q would allow quick swapping between the last two rows.

And for Hotbar Swap I have hotbarSwapBase bound to C, and then hotbarSwap1 bound to C + 1 etc. Then when I hold C I get the overlay/preview, and then pressing the corresponding row number, for example completing the C + 1 hotkey combo, I would swap with the first/highest inventory row.

So based on that GitHub page description, I think the only feature missing is the ability to swap and preview only a single column of the inventory, based on the selected slot. I guess I could add that at some point.