Block Variant Swapper

Holding the swap key shows a column of translucent slots over the hotbar, each naming one variant in the group, so a player reads the target block before committing to a placement. Holding Left Alt by default and scrolling cycles through the configured variant group, and the key can be rebound in controls. A held block is changed in hand without opening a crafting table or stonecutter, which removes the need to craft each variant by hand.

The core idea is that an entire family of blocks, for example oak building blocks, behaves like a single item for storage. Variants live only in the hotbar and offhand, and a smart pickup feature merges a base block picked up while holding a variant into the same stack. Breaking a placed variant drops the base block, so nothing is lost, and the mod reverts to the original base block whenever needed. Functional blocks such as chests, barrels and furnaces are not part of the family system.

The mod is open source under the GNU Lesser General Public License v3.0 only. Servers that run it need every player to install it too. Files are published for Fabric and NeoForge, with 1.21.1, 26.2 and 26.3 among the game versions covered.