Replace the system font family on Nokia
You will naturally need root to replace a system font. Because without root, you cannot write to the partitions where the fonts are stored and loaded from. 

So, in order to answer your question - No, it is not possible. 

That said, we do hear that Android Q will have support for font changes. If the feature makes its way to the final Q builds, you will be able to do font modifications when it hits your device in the coming months.