Replacement classes in ThinkGeo.Core 12.3.2

Thanks,
We are using .net5, Microsoft.SqlServer.Types is not supported in .NET Core.

Kindly suggest alternative which is supported in .NET Core.

We are using below code for CloudFileFeatureLayer and LayerDefinition.

LayerDefinition USTownshipAndRange = new LayerDefinition(“us_twnshp”, new RectangleShape(-178.285802, 71.468274, -80.031491, 25.138416),
GeographyUnit.DecimalDegree, 6, “http://thinkgeo-giseditor-cloudfilelayers-dev.s3-website-us-east-1.amazonaws.com/us_twnshp/”);
CloudFileFeatureLayer layerUSTownshipAndRange = new CloudFileFeatureLayer(USTownshipAndRange);
layerUSTownshipAndRange.FeatureSource.Projection = GetPLSSProjection();