There are many kinds of designers lumped into UX designers. There are visual designers, information architects, website designers, consumer app designers, usability engineers, interaction designers, UI designers, human factors engineers, user researchers, and I am sure that I could come up with more. The point is that there are different flavors and emphasis around different types of design within UX.
When you begin looking for a designer, do not get caught up in the tools and the specifics. Every designer needs to learn and adapt to the tools and specifics of a project or company. What you need to focus on is what kind of product that you need to design.
Most enterprise applications that I have worked with are very complicated, have many kinds of users and roles, require lots of configuration, have a lot of information, require huge amounts of setup, are transactional, and have stateful screens. Understanding the users, the business domain and the technology is essential to the creation and execution of good designs. So understanding how the designer works through this process, tools, models, techniques, negotiations, testing and validation.
All of what the designer shows and communicates has to be in the pursuit of simplifying this complexity for the user. They need many of the skills of each type of designer in UX but really needs to be deep in the area that is most challenging for your team. Many cases there is a huge gap in expertise in the enterprise team around interaction design and how a user can follow through this complicated system to get their job done with ease.
The trap that I frequently see is that enterprise software organizations typically have huge engineering teams and have rarely had designers. This in the end created “ugly” UIs so they decide they need a visual designer to make pretty UIs. Pretty UIs are done and then a lot of money had been spent to put “lipstick on a pig.”
Get the right designer and you can build the right product… Not just a pretty pig.