I saw Shuri holding a spear during the final battle in BP1 so I don't think it's crazy to assume she got basic training. But I doubt that she was given near the same level of preparation for the kingship. T'Challa shadowed his father his entire life and was pushed in every possible way mentally and physically to take over Wakanda, while she probably got the basic stuff for self-protection while choosing to focus on tech.
And I think it's pretty obvious that while she has a great scientific mind, she'd probably not want to do the diplomacy, fighting, and administration that T'Challa does on a regular basis because she wasn't pushed in that direction. In that case it wouldn't be sexism, it'd probably be because she's the younger sibling. Hell the way T'Chaka killed his own brother you'd think N'Jobu didn't have any combat abilities either lol.
It could be a matter of putting all your eggs in one basket since the Wakadan nobility is small and highly elite, maybe it's better to raise one really good royal candidate as opposed to several moderately good ones. Doesn't mean the secondborns like Shuri don't get investment in their talents, but it does result in different skillsets.
But she's still a kid and has a few more years in the MCU so it's possible that she might grow into it as T'Chadwick gears up to leave. I could see Coogler mixing her comic griot powers with a personal habit to give her some combat potential. And theoretically speaking I guess she could take her role as princess more seriously as Wakanda faces more threats. But I don't see Disney going for it unless they plan to have BP die within the MCU rather than just retiring from active superheroics.
Which I prefer tbh, because I think Shuri's character arc should be about more than claiming her brother's title. Coogler opened up all types of stories for her when M'Baku confronted her during the ceremony about how she scoffed at tradition. I'd want him to build on that and have her embrace the mysticism of Wakandan civilization rather than rejecting it. If we ever see a Shuri BP, it'd probably be when we start getting alternate universes and time travel, which I'd down wit.