No Problem doing this as long as you're using an Online License, which is the default license type.
A key feature of an Appeon PowerBuilder subscription is that it allows a subscription holder to install Appeon PowerBuilder on any machine, allowing the user to work from anywhere, however, the user will only be able to be logged-on to one instance of PowerBuilder at any one moment (Online License mechanism).
Open PowerBuilder on your Windows 7 machine ► On the top right corner, click on your account name ► Account Management ► "Sign out"
Now, on your Windows 10 machine, download PowerBuilder from your User Center: https://account.appeon.com/download
Once installed, simply log back into PowerBuilder with your Appeon account.
Cordially,
Mariano C.