I'm an engineer turned bus-dev/sales person. I found the transition very difficult and was recommended to sign up for sales coaching. It was excellent advice and I learned a lot about my inherent weaknesses when it comes to selling and how to compensate for them. I wrote a few of my lessons on my blog. A bit dated but perhaps of value to others:

https://www.curiousjuice.com/blog-0/bid/134157/Sales-trainin...

https://www.curiousjuice.com/blog-0/bid/135376/Secret-to-sal...