Is there a way to change text style while keeping specific words with another style?

Hi, I’ve been looking for a while if there is a way to do this but I haven’t found anything yet.
I have a paragraph of text with a style of “Body/Desktop/Normal” and then inside that paragraph I have a bunch of words with a style of “Body/Desktop/Bold”.

I already have existing styles created for the mobile version respectively.

Now when creating the mobile version I’m wondering if there is any way even if it’s through a plugin to change the paragraph in a way so that words that have “Body/Desktop/Normal” change to “Body/Mobile/Normal” and words that have “Body/Desktop/Bold” change to “Body/Mobile/Bold” but so far I have had any luck, any time I try to change the style of the paragraph the entire thing changes removing any specific styles I have applied.

Sure I could just change the whole paragraph to the normal style and then go through and apply the bold style again to every word but I was just wondering if there was a more automated way of doing it.

I hope I have explained myself properly, thank you for your time in advance.