How to See Locked and Unavailable Villager Trades
Open the Trading Menu
Walk up to any villager and right-click to open its trading screen, just like you normally would. With Visible Traders installed, the menu now lists every trade the villager knows, not only the ones you can currently use.
Read the Greyed-Out Entries
Trades you have not yet unlocked appear greyed out or dimmed alongside the active ones. These are the offers gated behind experience levels the villager has not reached. You can still read the input and output items on each row, so you know exactly what the villager will offer once it levels up.
Use It to Plan
Hover over a locked row to check the items involved. If a locked trade needs an item you do not have, note it before you start trading. This lets you decide whether it is worth feeding the villager emeralds to push it to the next level, or whether you should look for a different villager with a better locked offer.
Because the full list is visible from the first time you open the menu, you never have to guess what a villager might sell later. You can compare two villagers side by side and pick the one whose hidden trades suit your needs.