When creating the variant for replies and forwards, Letsignit will take this variant and automatically apply it to your replies and forwards instead of the main signature.
If you choose not to create this variant, your main signature will be automatically integrated into your reply and forward emails, like in every new email.
Here is a short video that will help you apply a reply/forward signature to your active signature.
The trash can icon will only remove the reply/forward variant, the original signature is unaffected.
If you use the Outlook desktop client together with the Letsignit App, you can manually change the signature you want to use for each email.
It is worth mentioning that this functionality is not available for webmail when using the API configuration. Similarly, campaigns are not included in the variant for replies and forwards.