The devs of Real Life™ really fucked up by not having a respec mechanic. Fortunately modders should be able to fill the gap once they figure out brain-computer interfaces and genetic engineering.
Honestly, I'm doubtful those are the answers. Most of the cybernetic enhancements to your brain would be be inferior to making your organic brain work better. The ones that are superior would be upgrades instead of respecs. Genetic engineering wouldn't be a respec as much as a redo of a bad dice roll for base stats. Many of the mistakes you make in your early life through choices can be solved by medicine healing injuries, extending life for more time to relearn, or by creating societal systems that allow people to right their wrongs.
Some amount of respeccing is possible, but it takes a lot of time and experience points – and characters with the Force of Habit trait are locked out of this respeccing mechanic, so their players’ only option is to delete their character once the game stops being fun…