Or indeed the earlier suggestion that ...
I would say that Larian should prevent swapping weapons after you make your attack, but what if you have 2 full actions and you need to melee one and snipe the other target.
I guess the choice of whether to disable weapon swapping after one weapon attack, or after all attacks, would then come down to whether we thought that our characters should be able to make a ranged and melee attack in a single turn. If I'm understanding what folk are saying about 5e correctly, only if they had at least three actions in one turn, as they'd need to attack with one action, swap to another weapon with another, then attack with that. So generally, most classes wouldn't be disadvantaged (compared to 5e) if they were stuck for the turn with the weapon set they first make an attack with, but I guess fighters could be?
RAW, you should be able to swap from melee to ranged or vice versa
once per turn for free, at any point during your turn, with the caveat that you drop your initially held weapon(s). Item-interaction Rules:
You get 1 free item-interaction (drawing OR stowing a weapon), and dropping an item is...not explicitly defined. RAW, you can change a 2H grip to a 1H grip at no action-cost, so it follows that you can equally go to zero hands with no cost. Dropping something would also qualify under "making gestures," which is listed as an example of something with no action cost.
If you didn't want to drop your initially held weapon, you'd need to spend an Action to Stow it.
This is a full action. Not an attack-equivalent action. Alternatively, I suppose you could just drop your held weapon on your next turn, and spend your free item-interaction picking up your originally dropped weapon..??? Assuming an enemy doesn't kick it away, this is equivalent to getting 1 free item *swap* each turn.
Of course, all the above only applies to switching 1 weapon for 1 other weapon, and falls apart if you're dual wielding or have something else in your offhand. To be able to draw/stow two weapons at once, you need the Dual Wielder Feat. A shield requires a full action to don/doff, as shields are intended to be strapped in, not just held.
