That being said

Hi,

A: So the key ingredient is really the fluoride. The rest of them, as you said, bells and whistles-the tartar control, the whitening. That stuff we don't really need.

B: No, you don't really need that. You just need to make sure to look out for fluoride.

A: All right. Very important. But that being said, if we can't use the whitening toothpaste, we really need to be careful about things that will stain our teeth, like soda, coffee, right?

Q1) Is the underlined part an example of absolute phrases/clauses?

Q2) So how does the transformation process go? Here is what I think.

As you said that, You really need to be careful~

=>You said that->That was said (by you)->that being said

Correct?

Q3) Is it possible to add "with" right in front of "that being said"?

=>With that being said,~ (?)

Q4) Is it ok to omit "being" in the underlined?

=> That said, ~ (?) Or With that said,~ (?)

Q5) How is "that being said" different from "that is said"?

I'd appreciate your help.