Here’s the thing about keyword research – the analysis is where its at. If you’re just barfing out AdWords data combined with some SEMRush crap, you’re not adding any value for serious search marketers.
However, if you’re doing competitive & category research and going deeper, you might be able to make a horse race of it. BUT. Selling that to someone who doesn’t understand makes an interesting challenge
Yet, it is one of the most important tasks in SEO but providing keyword research services is not a good business.
You need to provide complete SEO services to your clients. It is must only then you can prove that the keyword you researched for them is perfectly fine.
I see many SEO professionals offer keyword research as a service, so I think that if it’s a skill that you have then it would be smart to offer it, because even though it’s simple, simple may be just what clients are looking for.
Among useful keyword research software I can recommend there’s SEMRush, Zutrix and KWFinder