I'd imagine just about all of them and more - chisels, quills, brushes, acids, hammers, awls, pliers, rasps, rifflers, carving knives etc, just about every tool could fall into there minus maybe bellows and a few random things like that.
Outside of like a palette/tub, brushes/quills, and materials like ink, paint, or dye, and maybe an easel I don't see much requirement for many new specialty artistry tools.

I've seen alterers use a variety of tools, so I'd think it could depend on what you're doing.

Tooling/detailing of leather, detaililng of rocks/stone/metal/wood, embedding of stones/gems, adding fabric or metal edging, coloring/dying/patinas, changing the handle/haft/grip, as well as traditional paintings/images.

assuming that kind of stuff are all options.
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