I'm a system engineer. Some job openings are looking for a specific skill set, but most don't actually require all of the specific skills listed. If you have similar experience, even from college, the degree is what matters and your willingness to learn.
I recently accepted an offer from a company. In the job description, it mentions software XYZ, and I've never used XYZ before. But after a little research, I found out the company that makes XYZ also makes ABC, and I used ABC in college (9 years ago). So in the interview, I was able to explain my experience with ABC, and how I can leverage that knowledge for XYZ.
In most of my interviews, I've said "I've never done XXX before." But then from my resume, I say, before this project, I had never done this before either, and here's how I was successful. If their job description talks a lot about one topic, be sure to let them know you are able to handle it, even though you might not have direct experience.
I would look at system engineering spots too, no two companies have the same definition of that, and there are few degrees actually in it, most system engineers got their degrees in something else. They do a wide variety of things, not all are fun IMO, so be sure to understand the day-to-day.
I've known a few part-time engineers, and they had been at the company for years, then switched to part-time. It might be something you can talk to your current employer about, but I doubt you'll find a new position that's part time.