The following is a synopsis of all information concerning the focus components of spell and Primal/Divine Foci specifically written in RAW.
A focus component is defined as:
A focus is an object that funnels the magical energy of the spell. The spell gains the manipulate trait and requires you to either have a free hand to retrieve the focus listed in the spell or already be holding the focus in your hand. As part of Casting the Spell, you retrieve the focus (if necessary), manipulate it, and can stow it again if you so choose. Foci tend to be expensive, and you need to acquire them in advance to Cast the Spell.
A total of 4 spells that I can find have required focus components: Alarm (requires a 3 gp bell as a focus), Seashell of Stolen Sound (likely intended for seashell to be used as a focus), Plane shift (likely intended to require magical tuning fork as a focus), and Song of the Fallen (focus not specified in spell description).
A Primal focus is define as:
Because you're a druid, you can usually hold a primal focus (such as holly and mistletoe) for spells requiring material components instead of needing to use a material component pouch.
A Divine focus is defined as:
Because you're a cleric, you can usually hold a divine focus (such as a religious symbol) for spells requiring material components instead of needing to use a material component pouch.
Druids can take the level 1 Druid feat Verdant Weapon to:
You cultivate a seed that can sprout into a wooden staff, vine whip, or another weapon. You spend 10 minutes focusing primal energy into a seed, imprinting it with the potential of a single level 0 weapon you are trained with and that has no mechanical parts or metal components. When holding the imprinted seed, you can spend a single Interact action to cause it to immediately grow into that weapon; a second Interact action returns it to seed form. Your verdant weapon functions as the imprinted weapon and can be etched with runes or affixed with talismans as normal, which are suppressed when the weapon is in seed form. It also becomes a primal focus. You can have only one verdant seed at a time. If you prepare a second, your first verdant seed immediately becomes a mundane specimen; any runes on the previous seed that are valid for the new seed transfer between them at no cost, but you lose any inapplicable runes unless you transfer them to a runestone or another weapon.
Clerics can take the level 2 Cleric feat Emblazon Armament (CR 122) to:
Carefully etching a sacred image into a physical object, you steel yourself for battle. You can spend 10 minutes emblazoning a symbol of your deity upon a weapon or shield. The symbol doesn’t fade until 1 year has passed, but if you Emblazon an Armament, any symbol you previously emblazoned and any symbol already emblazoned on that item instantly disappears. The item becomes a religious symbol of your deity and can be used as a divine focus while emblazoned, and it gains another benefit determined by the type of item. This benefit applies only to followers of the deity the symbol represents. For shields, the shield gains a +1 status bonus to its Hardness. (This causes it to reduce more damage with the Shield Block reaction.) For weapons, the weapon the wielder gains a +1 status bonus to damage rolls.
Primeval Mistletoe is the only written item that specifies that it can be used as a primal focus.
Hundred-moth Caress is the only written item that specifies that it can be used as a divine focus.
With all of that out of the way Can a Primal or Divine focus take the form of a permanent held item such as a weapon, shield, wand, or stave?
To me, I see nothing in RAW that limits what form a focus can take. The presence of the Hundred-moth Caress and Primeval Mistletoe sets the precedent that foci can take the form of magical items and weapons. The class feats mentioned above allow for the rapid creation of buff weapons and shields with out the need for crafting checks. The weapons created with these feats can be used as foci, but the feats themselves do not suggests that weapon foci could not be found through adventuring or crafting (much like how an alchemist's ability to quickly create alchemical items does not limit non-alchemists from crafting or finding such items).
With all this laid out, does granting a Druid a primal focus in the form of a thematically appropriate staff weapon or wand break the game? Is it too strong? Does it take away from Druids that take Verdant Weapon? There really needs to be GM advice on this topic.
My feeling, base on RAW and my interpretation of rules as intended, is that any object can be a Primal or Divine focus as long as it fits the general description laid out in the class and must be held to use (i.e., worn objects as foci are not supported RAW). I think that to make a focus version of a basic item (ex. lvl 0, staff, common), a gm should likely reflavor it accordingly to fit the class description and then raise its level by 1 and/or increase its rarity (ex. lvl 1, primal staff of live oak, uncommon). An item such as this should probably only be given to a character through a formula or through adventuring.
What are the community's thoughts on this? And please don't say that we are limited to only the item's given in RAW. The GM guide very clearly supports the creation of items. The key questions are Do permanent held items that serve as foci break the game? Are permanent items that serve as foci directly or indirectly prohibited/discouraged by RAW? What guidelines should a GM use to create such items since so few have been published?