LÖVE

Is there any library or demo that has transformation and selection tools like in photoshop?
Where you can use it to move, scale and rotate stuff in the app? Also have selection tools like box select and lasso tool with highlight?
Maybe there is a pixel editor made in LOVE?
Alternatively maybe you know an utilities library that helps with that and I am also looking for a tween and timer library.

I don't see why you would need an image editor with all these tools made in löve. If you want a free image editor with these features, I recommend paint.net.

I am not making a paint editor, I am making something else but need to manipulate things like that with the transforms and selection in the app.

I don't believe such library exists in ANY language. Select & transform tools depends on your implementation of storing, rendering and picking objects.

You could try to find tiny open-sourced graphics editor and look at its code, but wouldn't it be easer to make these tools yourself from scratch?

Tweening/timer functions implemented in Lua you can find here for example: https://github.com/dinodeck/ninety_nine ... boxes/code (file "Tween.lua").