Will an AI civ have access to metal without [DIGGER:ITEM_WEQPON_PICK]?
The Metalsmith work group (furnace operator primarily/minimum, and other craft-smiths) establish basic metal minerals like copper, silver, iron and gold
regardless of picks, picks themselves don't determine access to minerals, those jobs to manufacture it do. Infact with custom reactions you can even make edged picks out of obsidian stone similar (not entirely, just as a base material) to obsidian swords, though picks don't need a edge to work like axes do.
If you don't want them to use basic metal (or any non pseudo metal) materials, custom reactions can substitute but might be very intensive with writing out your own lists of things to craft, like weapons armor, tools, furniture and misc objects. You can also give them fake access to wood by putting them in woodless biomes (or disabling access to OUTDOOR and INDOOR wood) then having crafting reactions to make weapon-grade (or below/varying levels of weapon grade) wood with the elf wood weapons & armor tags so they bring them on sieges.
- I learned the pseudo wood trick from mephs masterwork Naga race, who have faux wood 'coral' objects which are more dense because they have settlements in lakes. The obsidian and pseudo/alternative metal tricks i learnt while making my own playable elf fortress modifications, which converts combinations of special plants and seeds into metal bars to be used in custom craftshops.
- A axe made (entirely as base material) out of obsidian will cut wood well enough, but all obsidian weapons/tools can shatter against hard metal surfaces but generally do ok versus skin and flesh.