Hello,
If I understand you correctly, you want to use Default windows 10 style while still using windowblinds on other thing. If so you can right click on start menu -> configure Start10 -> Style . There are 3 style there you can choose. Windows 7 style, Modern Style and Windows 10 Style. Usually Windows 7 style with windowblinds theme was selected by default. But you can choose those other two which is slightly faded out. Just click on "Windows 10 Style" and you will get what you wanted.