You can only take the Item crafting and Metamagic exploits once correct?

[Alchemist 23]

For Arcanist you can not take the extra feat exploits more than once correct?

Are there any that you can take multiple times?

[GM Rednal]

Arcanist Exploits wrote:

An arcanist exploit cannot be selected more than once.

If there's an exploit that's an exception to this, it will clearly and specifically say so.