public class Foo
{
    public DateTimeOffset DateTimeOffset { get; set; }

    public DateOnly Date { get; set; }

    public DateTime DateTime { get; set; }
}

TypeAdapterConfig<DateTimeOffset, DateOnly>.NewConfig()
    .MapWith(s => DateOnly.FromDateTime(s.UtcDateTime.Date))
    .AfterMapping(s =>
    {
        Console.WriteLine("From DateTimeOffset to DateOnly");
    });

TypeAdapterConfig<DateOnly, DateTimeOffset>.NewConfig()
    .MapWith(s => new DateTimeOffset(s.ToDateTime(TimeOnly.FromTimeSpan(TimeSpan.Zero)), TimeSpan.Zero))
    .AfterMapping(s =>
    {
        Console.WriteLine("From DateOnly to DateTimeOffset");
    });

TypeAdapterConfig<DateTimeOffset, DateTime>.NewConfig()
    .MapWith(s => s.UtcDateTime)
    .AfterMapping(s =>
    {
        Console.WriteLine("From DateTimeOffset to DateTime");
    });

TypeAdapterConfig<DateTime, DateTimeOffset>.NewConfig()
    .MapWith(s => new DateTimeOffset(s, TimeSpan.Zero))
    .AfterMapping(s =>
    {
        Console.WriteLine("From DateTime to DateTimeOffset");
    });

var foo = new Foo();
foo.DateTimeOffset = DateTimeOffset.UtcNow;
foo.DateTime = DateTime.UtcNow;

Console.WriteLine(foo.DateTimeOffset.Adapt<DateTime>());
Console.WriteLine(foo.DateTime.Adapt<DateTimeOffset>());