Yes. I cannot edit range of spell itself neither an extension effect.
But I can change range of each of effect (AC modifier and so on) into party. And then it works.
Or do it The Imp's way
Thanks for your help. I can change Skald's song, Jester's song. I don't know how to change vanilla bard song, but it is not necessary. I need only Skald's one.
Have a good day, I will come back soon