Just here to clarify that the reason, or at least one of the reasons, that this is not yet implemented is technical limitations. Unlike Tera types and moves, which you can view in JSON format
here, items are not picked from a list but rather assigned according to lots of rules. Thus, the /randbats command cannot simply get the data from the source. The way some other data repositories like
this one have the possible items is simply by generating a gazillion teams and seeing what they end up with. This data then flows to other projects, like the rands damage calculator. That means it's possible for very rare items to be missed, and unlike the /randbats command it's also not guaranteed to be up to date.
Furthermore, the item generation rules are sufficiently complex that giving a list of items might not be enough to reasonably inform the player. For example, Masquerain in Gen 6 has about a 1 in 200 chance to have Choice Specs. Telling the player that it has "Choice Specs, Focus Sash, Leftovers" might be more misleading than helpful. To the best of my knowledge, no such edge cases exist for moves and Tera types.
This is not to say that the suggestion shouldn't be approved, just that the implementation is more complicated than it may appear, and that any solution would include tradeoffs that need to be thought about carefully.
