The Polo isn't offered in the US, so my technical info is very limited. However, I'll try to help.
Are you getting spark and fuel to the engine? I noted that you replaced the crank sensor which is usually the cause of no ignition spark. Also, is there any chance of engine timing being off? Does the engine sound normal when cranking? Is it possible for you to record the engine cranking and uploading it for me to hear?
Tell me, if you use starting fluid, does the engine start for a couple of seconds and then stall?
Here is a link you may find of interest. Take a look through it to see if anything helps. Also, let me know if you can make the recording and upload it for me.
Let me know.
Sunday, November 8th, 2020 AT 6:47 PM