So i installed lxqt with kwin. Is there any way that I can change the kwin theme without installing kde systemsettings.
that would be impossible, even if you install lxqt)kwin-integration-extra in aur, you also take a lot deps 
but that would be the only way without systemsettings…dep wise i think does not mather…
but you can with the integration using the klockscreen also , https://aur.archlinux.org/packages/lxqt-kcm-integration-extra-git/
https://aur.archlinux.org/packages/lxqt-kwin-desktop-git/#pinned-726803
When you say theme, what are you referring to, the window decorations?
I believe those are stored in ~/.config/kwinrc. That being said, it requires some pretty specific config there. Certainly not something you want to mess with unless you have a feel for how it all fits together.
yeah something like that
lot of deps…
idd kwin itself also a lot of deps offcourse imp more a lxqt-xfwm4 user then kwin currently i’m busy with a wm only setup
i tried openbox only desktop with polybar rofi plank etc but i cant make it look right
You can TRY using kvantum or qt5ctl as they can theme apps as well.