Firstly, I'd recommend having a closer look at the ways in which the courses differ by looking at the module break down/course content for each degree. You should get an idea of how much overlap there is, how much opportunity there is to learn material from the other specialism, etc.
I'd also definitely recommend going to an in person or virtual open day and talking directly to the staff/students there, as they'll be able to give you the best idea of which course to go for based on your particular circumstances, specific interests and career goals, as well as the different jobs graduates pursue.