I assume you mean for the blacksmith.
Hammers - Can wield either head, I think - 2 or 3 bars heated, blunt heads, one hand grip - equip with.. e? I think, it always but maybe that's configurable - whatever your interact button is aside from clicks. Must have hammer slot selected for "new" hammers to be equippable
Pickaxe - can be any grip, just needs a proper head - can equip first pick from any slot, but once there is a pick, must select pick slot to equip new picks.
Hatchet - Must be small-ax head, can be one or two hand grip same as Pick otherwise.
To Change select head for Smithing - You must have a specific number of heated ingots on anvil.
1 Heated ingot on Anvil -> Small blade/Knife
2 heated ingot on Anvil - > Small Blunt head, Small Ax head, normal blade
3 heated ingots -> Large Blunt head, Large Ax head - Large Ax head is also Pickaxe head (Must be struck again), large blade.
Any Blade + pole grip = Sellable Polearm
Any Hammer head + polegrip = sellable polearm
Axe+pole =/= Sellable
_________________
2h Grip + Pickaxe head = "Pickaxe" (sellable/customer recognized)
1h grip + Pickaxe head = nothing, But Blacksmith can recognize it for personal use pickaxe
__
1h grip + small ax head = "one hand ax" (I call em Hatchets)
2h grip + small ax head = nothing - but Blacksmith can recognize it for personal use hatchet