Hi,

I can't find anything about setting paramter values in nodes with vex. I know, how it's done with python. But I'd like to do it from inside a wrangle node. Any hints?

Something like pseudocode:

Vex is not a scripting language, so no it cannot do that. houdini control operations can only be done with python or hscript. Think of VEX as a shader language. It works on data and applies a set of instructions across that data. The scene itself is not among the classes of data available to VEX.