This issue has been closed & locked as .NET Core 3.1 support was introduced with the Plato 1.1.0 release.
We are committed to ensuring Plato supports that latest technology stacks and to ensuring you can use Plato on the latest long term supported version of .NET Core..
Our Plato 1.1.0 release (currently in preview & due in early February 2020) introduces support for .NET Core 3.1. .NET Core 3.1 will be a long term support or LTS version of .NET Core and will receive extended support from Microsoft. For further information please see the official .NET Core Support Policy.
Plato - Better Together