PHP Only solution on pageload

Hello,

as I want the CLS and the LCP of the web-vitals as low as possible i wanted to ask if you have a hint for me how to use your php functions to implement the swatches directly on pageload with the initial html answer and add the functionality for switching async. I already found the functions you use in the functions files but i stumble to select the right one with correct attributes.

Regards,
Martin