public partial class Address
    {
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
        public Address()
        {
            this.Accounts = new HashSet<Account>();
            this.UserAddresses = new HashSet<UserAddress>();
        }
    
        public string Id { get; set; }
        public string City { get; set; }
        public string Street { get; set; }
        public string House { get; set; }
        public string Corpus { get; set; }
        public string Flat { get; set; }
        public string SecretWord { get; set; }
        public Nullable<bool> IsVisible { get; set; }
        public string OwnerId { get; set; }
    
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
        public virtual ICollection<Account> Accounts { get; set; }
        [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
        public virtual ICollection<UserAddress> UserAddresses { get; set; }
        public virtual User User { get; set; }
    }

public class AddressDTO
    {
        public AddressDTO()
        {
            Id = Guid.NewGuid().ToString();
            this.Accounts = new List<AccountDTO>();
            this.UserList = new List<UserDTO>();
        }

        public string Id { get; set; }
        public string City { get; set; }
        public string Street { get; set; }
        public string House { get; set; }
        public string Corpus { get; set; }
        public string Flat { get; set; }
        public string UserId { get; set; }
        public string SecretWord { get; set; }
        public string OwnerId { get; set; }

        public virtual ICollection<AccountDTO> Accounts { get; set; }
        public virtual ICollection<UserDTO> UserList { get; set; }

        public override string ToString()
        {
            return string.Concat(City, ", ", Street, ", д. ", House,
                                string.IsNullOrEmpty(Corpus) ? string.IsNullOrEmpty(Flat) ? string.Empty : ", кв. " + Flat : ", к. " + Corpus + ", кв. " + Flat);
        }
    }

Mapper.CreateMap<Address, AddressDTO>().ForMember(x => x.UserList, w => w.MapFrom(n => (from u in n.UserAddresses select u.User).ToList()));

List<AddressDTO> addressIdList = Mapper.Map<List<Address>, List<AddressDTO>>
                ((from address in _database.UserAddress.GetAll() where address.UserId == userId select address.Address).ToList());

var userList = (from u in n.UserAddresses select u.User).ToList();

.ProjectTo<AddressDTO>()

var addressIdList = _database.UserAddress.GetAll()
   .ProjectTo<AddressDTO>()
   .Where(p => p.UserId == userId)
   .ToList();

_database.UserAddress.GetAll()