Creating new sprite sheet from attached sprites/textures of SpriteRenderer Components

Hello, I would like to know if it's possible to generate a new sprite sheet of more than one sprites from different (already made) sprite sheets (like an arm from "Arms.png" and/or eyes from "Eyes.png") and take them/"place them" into a completely new created sprite sheet (may also set the positions of these in this new texture).

Because I have a 2D Character, I can select each pody part of it at runtime via buttons. Now, if I selected every part I want to "export" all selected sprites (which are, of course, from different sprite sheets) to another (new generated) one, after (e.g.) I pressed a button named "Save as sprite sheet".

I have to say, that each body part texture (multiple textures, single sprites were selected in the Sprite Editor of Unity) is attached on a SpriteRenderer and this SpriteRenderer is a component of a Child. This Child can be "Arms", "Face" or "Legs" (something like that) and you can see it in the Hierarchy of Unity Editor. The Parent is the "Character" Object (Empty Object)

So, can you tell me if it's possible? Because this would help me a lot, to save created Characters as a "prefab" (not really, but then I have a sprite sheet and that would be great!).