Handling DateTimeOffset in Entity Framework Core 3.0 with SQLite, see https://blog.dangl.me/archive/handling-datetimeoffset-in-sqlite-with-entity-framework-core-in-test-scenarios/

DatabaseContext.cs

protected override void OnModelCreating(ModelBuilder builder)
{
    base.OnModelCreating(builder);

    if (Database.ProviderName == "Microsoft.EntityFrameworkCore.Sqlite")
    {
        // SQLite does not have proper support for DateTimeOffset via Entity Framework Core, see the limitations
        // here: https://docs.microsoft.com/en-us/ef/core/providers/sqlite/limitations#query-limitations
        // To work around this, when the Sqlite database provider is used, all model properties of type DateTimeOffset
        // use the DateTimeOffsetToBinaryConverter
        // Based on: https://github.com/aspnet/EntityFrameworkCore/issues/10784#issuecomment-415769754
        // This only supports millisecond precision, but should be sufficient for most use cases.
        foreach (var entityType in builder.Model.GetEntityTypes())
        {
            var properties = entityType.ClrType.GetProperties().Where(p => p.PropertyType == typeof(DateTimeOffset)
                                                                        || p.PropertyType == typeof(DateTimeOffset?));
            foreach (var property in properties)
            {
                builder
                    .Entity(entityType.Name)
                    .Property(property.Name)
                    .HasConversion(new DateTimeOffsetToBinaryConverter());
            }
        }
    }
}

DateTimeOffsetTickSubtraction.cs

// SQLite only stores up to .001 second precision due to the
// internal conversion to long / unix timestamp
var ticksToSubtract = myDate.Ticks % 1000;
myDate = myDate.Subtract(TimeSpan.FromTicks(ticksToSubtract));