Currently if you want to use Outsytems OOTB send email actions in your different applications, they will all share the same SMTP configuration set for the environment in Service Center.
Let's say you have 2 different applications with different branding, both with email sending functionalities. If you want to set a different SMTP profile for each one (e.g.: unique sender name, SMTP server...) you actually can't... at least in an easy way as you would expect.
There are some forge components which allow you to create multiple SMTP profiles and map them to your desired espaces, but they essentially use custom send email actions which do not take OS OOTB email screens as arguments (you have to manually pass the raw HTML, do some regex tweaks, and a whole bunch of inline CSS in order to get it properly formatted)
This gets even worse in terms of scalability, imagine you already have an app (let's call it A) running in your environment making use of the default OutSystems send email action, and now you have to develop a new one (B) that needs a different SMTP profile... You have two options:
1. change A to use a custom send email action along with B (extra effort)
2. manage A's SMTP details in service center and B's in the custom component.
neither of both feels like an easy or elegant way to solve a problem that most would assume to be a 5-minute configuration.
It would be great to enhance service center's email section to accommodate multiple SMTP profiles and select which modules should each be mapped to.
Notes:
SMTP Forge Component here addressed: https://www.outsystems.com/forge/component-overview/1226/smtpclient