collectible replica weapons and their purchase

I have an interest in collecting weapons from different eras, including replicas of swords and firearms. I don't intend to use this as a form of intimidation; it's purely aesthetic. The question is, is it legal to buy replica guns from companies like Denix online? I read the gun law in Germany and saw that purchasing is allowed, but obviously carrying in public places is strictly prohibited, which is not something I wanted to do. Also, transportation should take place closed, in a cover or case, but with the appropriate documents, I think it will be fine. Are there anyone who has a similar hobby?