Neither of my kids have Scottish accents. Both DH and I have Scottish accents and have never lived outside of Scotland. I have a Glaswegian accent and DH has a very soft Edinburgh accent.
We live and the kids grew up in Fife, but both of them sound English. They both moved to England at 18 for studies (over a decade ago now) and people will ask them if they have Scottish family or links because they’ve very Scottish names, like Angus McLeod etc.
They only used to have a very slight accent, but DD said she put this on so she wouldn’t get teased at School