public abstract class EntityBase(string id)
{
    public string Id { get; } = id;

    public long RowVersion { get; }
}


public record OwnedEntity(DateTime CreationDate);

public class EntityA(string id, bool someValue,  OwnedEntity? owned) : EntityBase(id)
{
    protected EntityA()
        : this(null!, false, null)
    {
    }

    public bool SomeValue { get; } = someValue;

    public OwnedEntity? Owned { get; private set; } = owned;
}

public class EntityB(
    string id,
    string name) : EntityBase(id)
{
    protected EntityB() : this(null!, null!)
    {
    }

    public string Name { get; } = name;
}

public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options)
{
    protected override void OnModelCreating(
        ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<EntityBase>(
            b =>
            {
                b.HasDiscriminator<string>("Type")
                    .HasValue<EntityA>(nameof(EntityA))
                    .HasValue<EntityB>(nameof(EntityB));

                b.HasKey(x => x.Id);
                b.Property(x => x.Id).HasMaxLength(10);

                b.Property(x => x.RowVersion)
                    .IsRequired()
                    .IsRowVersion()
                    .IsConcurrencyToken()
                    .HasConversion<byte[]>();
            });

        modelBuilder.Entity<EntityA>(
            b =>
            {
                b.Property(x => x.SomeValue);
                
                b.OwnsOne(
                    x => x.Owned,
                    x =>
                    {
                        x.Property(x => x.CreationDate);
                    });
            });

         modelBuilder.Entity<EntityB>(
            b =>
            {
                b.Property(x => x.Name).HasMaxLength(100);
            });
    }
}

const string id = "SOMEID";

await using var dbContext = MyContextFactory.Create();
var entityA = await dbContext.Set<EntityA>().Where(x => x.Id == id).SingleAsync();
   
dbContext.Remove(entityA);

var entityB = new EntityB(id, "Any");

await dbContext.AddAsync(entityB);

await dbContext.SaveChangesAsync();