Refresh villager offers randomly per day (or week / month)

(Sorry for my enlish)

There would be a chance to re-choose one or more villagerss offers. For example: expert toolsmith can selling one week diamond axe and buy diamonds and after (random chance every day? Or every week or month?) re-choose offers - for example,  next week can selling diamond axes and diamond shovels as expert. This is important, couse player has to killing villagers for got better and different offers, or have to spawn 5 toolsmiths villagers for more variations of all offers insted of have one or two toolsmiths in one village. If toolsmiths changing offers, player need few toolsmiths and observe theirs (weekly?) offers and dont have to killing villagers by lava etc.