The NIST frameworks were designed as flexible, voluntary frameworks. The fact that they are flexible makes it relatively easy to implement them in conjunction with ISO 27001.
This is largely due to both standards having a number of common principles, including; requiring senior management support, a continual improvement process, and a risk-based approach.
https://www.6clicks.com/blog/how-do-iso-27001-and-nist-csf-complement-each-other