I agree with this...it rings with intuitive truth. What we perceive as past, present, and future are all intimately connected and happening at once.
But I still say it's not about the "planning". It's about the being and the doing, the love and the forgiveness. Because the OP wanted to know about karma, and presumably about making good karma everywhere, in all incarnations.
There is no other way but authentic love and forgiveness, all round.
It will radiate out from your current expression to all others. Likewise, when you hate or harm others in other lifetimes, that too radiates outward to your current expression. Everything connects and radiates out in all directions. But the quantum and spiritual reality of interbeing is that first and foremost you are you everywhere...and what you do here immediately has impact on all other "you's" elsewhere, and vice versa. As well as on those you touch here or elsewhere, of course.
Now -- if you are able -- then yes, consciously go into those other identities you embodied (or embody elsewhere), consciously engage with those you loved (or for some of us, with those you hated) and make good where you failed others, in the spirit realm. Speak to them directly of your love, your forgiveness, your contrition...and let the truth illuminate your visage
. Let your presence speak your truth.
That way is more direct...but simply being and doing love and forgiveness works just fine, too.
Peace & blessings
7L