Don’t do it plwaseeee. I’m an SEO specialist. It confuses Google and will have the opposite to intended affect. It shows Google you are trying to trick them. You want a clean online presence with one website to rank and everything pointing there. You’re better off optimising your website further and sharing on social media regularly
Treat Google Business Sites like a citation and optimize accordingly. I've tested this a lot and using it like a citation for your main website helps... Just make sure you don't accidentally swap over the GBP URL's when you update it though.