Need some advice about keeping a strong email reputation when asking for backlinks

Hi, i'm looking for some advice on email reputation...

For a website I have a daily/weekly newsletter that gets sent to subscribers - I am using Sendgrid to do this and my reputation is 99% at the moment (shown on my Sendgrid account).

I need to do a lot of cold emailing but want to ask before doing it.

If I am using x@webdotcom to sent the newsletter and use y@webdotcom for cold emails. What if the y email gets a bad reputation, will it affect x? How can I approach this. I have never done cold emailing before and the reason I will be doing it is to approach website owners for backlinks to my content.

I has an idea to use a different email for this as I have several domains registered (.com/.org/.co/.me/.xyz) all forwarding to the main site, but thought this might give them a red flag when considering to link to my site.

Any advice is appreciated.