As far as I understand Wishlessness means that there is no suffering or ignorance as such.
If I were to try to relate that to the language of the suttas, I'd equate "wishlessness" with "non-craving".
And non-craving might exist might exist in two forms -- i.e. with, and without, the conditions for future craving to arise -- the former being intermittent (although also timeless or ever-available) and "a small taste of Nibbana", and the latter being final.
I feel like I get it, like there are no individuals existing as such
I think the Mahayana doctrine, at least as it's explained to beginners by e.g. Thay Thich Nhat Hanh and/or HH the Dalai Lama, is that there are "no individuals existing as separate" (or perhaps, "as individual") -- furthermore than a view of individuals as separate would be a cause for suffering.
there is no suffering as such
By analogy perhaps that means "no suffering as separate" -- i.e. that suffering is conditioned.
there is still (metta/compassion) the inclination to reducing suffering
I am particularly interested in the relation between Wishlessness and Love
What can I say. The sutta which narrates the Buddha's becoming liberated says that it was because of compassion that he then decided to teach.
So "the relation between Wishlessness and Love" in a Buddhist context might be that, that's the characteristic of the (perfectly enlightened) Buddha.
You could read a lot of what the suttas say about it, and essays, e.g. by searching https://accesstoinsight.org/ for the word "metta" -- and also more generally "brahmavihara".
The suttas sometimes describe metta is being like a mother's love, who would give her own life for child. I don't know that that's a good analogy -- easily understood by everyone --- because some people's relationship with their mother becomes complicated.
I don't know if you can understand something by understanding its opposite. A hypothetical example of "wishfulness" when parenting could be something like, a mother saying to their child, "The neighbour's child takes ballet lessons, and they're good at it, which makes their proud parents look good, which I envy. So I want you to take ballet lessons too." Whereas instead "wishlessness" might be more like, "may you be well", still providing all the "requisites" that a child can use to develop -- physical requisites like food and shelter, clothing and medicine -- also being a "good friend", age-appropriate lessons, maybe a moral environment.