This thread from early 2021 held promise for WinForms support in .NET core :-
We’re looking to move our developments forward and are going to come to a cross roads in spring 2024 as to which way to go. The key questions :-
At the moment am I right in thinking that designer support is not supported in .NET core when coding an Elements project ?
If it is still planned, can you give some reasonable firm indication of when ?
At present our other 3rd party provider does support .NET 7 in designer (DevExpress sample shown in VS 2022 below).
If WinForms designer support isn’t on the horizon, having to create and manage all components in code is a big ask. Our alternative path would be to look to continue using DA and Hydra, but doing it from Microsoft C# projects. Over time we’d have to rework all of our Elements .Net Framework code into C# .Net Core. I really don’t want to have us do that. Can you offer up some hope ?!
.NET Form Designer support for Core is still locked to VC# and VB, by Microsoft, there’s nothing we can do about it. It’s f***ing stupid, but it’s what Microsoft decided to do.
DeveXpress does not, as far as I know, provide their own compiler or project system, so that’s I assume a Visual C# or Visual Basic.NET project. The designers support third party components, they are just explicitly hardcoded to not allow use with third party languages. Why? I don’t know.
Can you offer up some hope ?!
I’m afraid we’re both at Microsoft’s mercy, here :(.