Right now, you can only configure completely hiding the HUD when you're not sneaking, but it would be nice if you could configure what information shows up when sneaking. For example, the default HUD just shows the coordinates, facing, and FPS, but sneaking will add more information like the entity count.

This would probably be done by modifying the enable flag for each setting to three values instead of two, where it's enabled/require sneak/disabled instead of enabled/disabled.

This is more likely to come after the mod rewrites from 1.12.2, where it's planned that you can add multiple info HUDs. I could add a configurable condition for the HUDs so that sneaking is required to show it. Then you can put the "only while sneaking" info in the separate HUD area, and place that for example below the normal always-visible HUD.