Hi @philippdgr. I’m sorry for the confusion there.
However, please let me make this clear:
We never automatically subscribe anyone to anything. Never.
When you install MetaSlider there should be a clearly-labeled modal window. The window asks you to confirm your email address and if you want to hear from us.
If you agree, we send you an email afterwards. If you don’t agree, nothing at all happens.
Please let me know if any of this process did not happen for you.
This seems like a very standard and normal practice for WordPress plugins, but we are absolutely open to changes if this process is not correct.