I'm talking about linking out naturally, NOT getting links in return or getting paid. Will it help with seo?
Of course you don't pick up link juice, linking out. But I have had some success linking to wikipedia for terms relevant to my keywords.
Linking out to high-authority sites in your niche (not wikipedia) has been shown to increase authority of your own site and therefore rankings. I'd recommend to do it, especially from your PBN.
Moz and other websites they do recommend 60 // 40 ration is necessary to avoid link velocity so it's better if you make few links with do follow and few with no follow that going to help your ranking to increase it's destiny.
of course High domain Authority links based on your niche (relevant) sites helps you to increased google Ranking & Trustworthy backlinks for your site to earn Google Ranking.
Yes, Google will consider your content to be more of a resource if you link to authoritative and related posts in your content and it will help you. It also gives Google a better understanding of what your content is about and what to rank you for. It is not just inbound links that help you with SEO but outbound links can also help.
It will be beneficial as it would improve your site's authority and credibility and therefore becomes a powerful off-page technique. Associations with the top sites of your niche can be a good thing in the long run. There are several ways to go about it, you can either mention their works on your social media profile to get their attention, take inspiration from their content and credit them to build a positive impact etc.