Can you get into product marketing by moving from a digital marketing role?
Yes, the easiest way to make this transition is to try to move into the Product Marketing org in your current company. I recommend getting to know some of the folks on the Product Marketing team. Ask them about their jobs and figure out if there are things you can do in your current job to prepare you for a role in product marketing. If you feel comfortable, set up time with the head of the team and express your interest in some day working in product marketing. This way, they will know of your interest should a role open up.
Finally, if you are going to start exploring roles in Product Marketing, you may also want to let your current Manager know of your interest. Depending on their approach to career development, they may be open to helping you make that transition to a role in Product Marketing.
It is certainly possible to move into Product Marketing from a Digital Marketing role.
Look a bit more holistically, where are you now in terms of knowledge and where you want to be? Which gaps you should fill and how? What can you do to get to where you want to be?
Here are a few options (please note below are only a few suggestions that worked for me, but you need to figure out what works best for you):
1. Consume product marketing-related content to get familiar with the attributions, the challenges and the lingo (podcasts, newsletters, articles etc).
2. Try to join communities that focus on Product marketing (eg Sharebird, PMA's slack channel, etc)
3. Connect with and follow other product marketers and learn from their experiences. (See Linkedin)
4. Try to join mastermind meetings where you can share challenges with other product marketers and maybe help them solve theirs.
5. Take a Product Marketing-related course. There are a couple of courses from CXL and PMA, plus several other function-specific courses from experts for Messaging and Prositioning, Competitive Intelligence, etc.
Also, there are several transferable skills, you just need to make sure you have some example that can illustrate those skills.
Research skills/Data-driven - Before creating a campaign you will look to collect and analyze the data and the insights and then apply those to your campaign (eg from different channels, users, ambassadors/ advocates or even press releases etc.). So try to illustrate how and where you look for data, how you decide which one to use and what results you have as a consequence.
Cross-collaboration - Product Marketing relies a lot on collaboration with many colleagues from different departments. Think of an example where you can illustrate how you worked together with other colleagues and what was the result. It can even be an internal initiative and the target audience could've been your colleagues.
Communication skills - This one ties partially with the cross-collaboration skill. In Product Marketing you work with so many stakeholders and you really need to influence people without directly managing them, plus there will be times where you will need to be firm and bring arguments while at the same time keep a good level of collaboration. Also, depending on the size of the company you might need to do presentations (internal/external).
Writing skills - A Product Marketer or Product Marketing Manager is a content architect. You know what you want to transmit, to whom, where and how, and work closely with a copywriter to bring that vision to life. If you are a skilled writer, that is even better.
Empathy - now this is a big one that'll help you both in the relationships with your colleagues and with you customers. It's going to make it easier for you to understand where they come from and communicate from the right angle. Considering that as a Digital Marketer you also get to create ads that speak to the pain points your clients have, you can understand what they need and you (aka the company) can help them and also support them in getting their jobs done.
Bonus* This one is quite generally valid for any job in Marketing) Problem solving - Try to think of an instance in which you were able to solve a problem. What was the problem, how did you approach it, what was the result?
Hope the above ideas can provide a starting point.