You can use achieve below functionalities in ACS with AEM:
Integrated cross-channel content authoring: Build template-based emails in AEM with access to Campaign’s email authoring tools including: subject line, responsive preview, inbox rendering, send proof
Leverage all your Assets in one place: Select images from AEM Assets, Edit and personalize text & images and Configure content blocks, add email specific links and publish directly to a delivery in Adobe Campaign
Seamlessly build tailored content for all: Personalized images for email, Name, email, ID, attributes can be added, Insert coupon codes in images
Automate newsletters: Create recurring email campaign content. Once the creative is in place, simply swap the content of the email in AEM to be delivered when you decide
Unified customer data & personalization :
Easily create, update and leverage contact profiles in Adobe Campaign based on data in Adobe Experience Manager
In AEM, you create forms with dedicated components respecting typology rules of Adobe Campaign
You map form fields with Adobe Campaign fields
You select the Adobe Campaign service subscription associated to your form & finally test it