Say I exchange links with a website and we both decide to put our links on our sites, sitewide. We both use dofollow at the beginning but after a week I change his link to nofollow. Does Google see this as a one way link or still reciprocal?
Why don’t you use a triangular link exchange? Ask the other person to put a link on his website to your main website, and from another website of yours you post a link to his website. In this case you don’t have a directly exchange links between your main website and his.