Is the effect better if I get shoulder fillers and trapezius Botox together?

I've been worried about rounded shoulders since I was young, and I've consistently tried to correct them through exercise, but I realized there was a limit.

While looking into shoulder fillers, I heard that getting them together with trapezius Botox makes the line improvement look more natural.

But I'm not sure if it's okay to get them together, or if I can get a sense of how much of a difference there is in effectiveness.

For those who have received both, how was it?