Thank you, i found the way to using “UStaticMeshDescription” for create UStaticMesh.
For anyone who need this, you can find example to create/edit your mesh in UStaticMeshDescription::CreateCube
Ex:
UStaticMesh* staticMesh = NewObject<UStaticMesh>();
UStaticMeshDescription* staticMeshDescription = UStaticMesh::CreateStaticMeshDescription();
FPolygonGroupID polygonGroupId = staticMeshDescription->CreatePolygonGroup();
staticMeshDescription->CreateCube(pass_parrams_here);
staticMesh->BuildFromStaticMeshDescriptions(staticMeshDescriptions);