Is there a work around google disabling “Less secure apps”?

You could try authentification via “App password”.

On your Google account:

1. set 2-Step Verification ON

2. create 16-character “App password”(
   How to create app password) -> result should be similar to:
   16-character “App password”

3. Instead of Google account password use 16-character password

   MailMessage mail = new MailMessage();
   foreach (string receiver in DolociPrejemnike())
       mail.To.Add(receiver);
   mail.From = new MailAddress("[email protected]", "No replay"); //pošiljatelj (vedno enak)
   mail.Subject = SetSubject();
   mail.Body = SetBody();
   mail.IsBodyHtml = true;
   
   SmtpClient smtp = new SmtpClient();
   smtp.Host = "smtp.gmail.com";
   smtp.Port = 587;
   smtp.UseDefaultCredentials = true;
   smtp.Credentials = new System.Net.NetworkCredential("[email protected]", "xtqapucsmyvqmvxp"); // Enter seders User name and password  
   smtp.EnableSsl = true;
   smtp.Send(mail);