Backlink coming from a new post vs coming from an old post

Hello folks,

I have the opportunity to get a do-follow backlink from an authoritative magazine. I have the option to get it from an old, ranked article, but with no customisation of the content that therefore will be slightly less relevant, as the magazine is in a parallel industry of my money site, or I can send them a full article (that I can customise as I want, with anchor text and content, therefore making it talk about the direct industry of my money site) and they will publish it as a new post.

Which one has more SEO power?

The new post is better.

The old article is already indexed and sometimes has new incoming links but it really doesn’t matter when you have authority mag.

I advise you to do the following thing: see what page of the magazine has the best metrics, then ask them to place the link on that page.