If you want just to send emails without upwards (or any) reference, you can call the actionSendEmail in the module EmailExtended_lib. The action receives almost the same parameters as theEmail node, so it's pretty straightforward to use. TheSendEmail action relies on OutSystems Email libraries, this means that email logs and dispatches to the SMTP server act like normalEmail calls.

If you want to set a different test email list for each project/application/module/email/project, you can use the Email Extended app to configure as many list as you want. For each list, you can specify which emails addresses () you want to redirect them to.

The EmailExtended_lib also include helpers to validate the email addresses.
To validate we can rely on regex validations, or we can rely on the parser provided by the .NET Framework. We can parse an email address using the MailAddress class, which internally use MailAddressParser. Email_isValidEmail action uses this parser to validate an email address.

Having an email address marked as valid, doesn't mean we'll be able to send an email at this address. If the user types "john@doe.dom" instead of "john@doe.com" (".dom" instead of ".com"), we may email a domain that doesn't exist.

We can avoid this kind of typing errors by checking the provided domain exists and has an email server. Indeed, when you email a recipient, you must first ask the IP address of the email server of the recipient. This information is provided by the DNS server, and more specifically the MX or A entry.
To query the DNS server in .NET, we can use the NuGet package DnsClient (NuGet, GitHub) which support .NET and .NET Core.  Email_isValidEmailWithDNSCheck will do that.