Unfortunately the question framed as "European" is very broad.
Every country is different and within these many venues do things differently.
My wife is visually, mobility and cognitively disabled and I research every country we drive to and every museum or other venue before travelling there.
Now EU narrows it down to around 26 countries, and Schengen would narrow it further, but if you could share a bit of your itinerary we may be able to help further.
Then there are the edge conditions - the EU design blue badge parking placard from the UK is valid in the Netherlands. That didn't stop an operative from Hoofddorp police from giving me a 310€ parking ticket for using a "not valid parking pass" in a disabled space at a rest area on the A4 near Schiphol airport. My wife needs those spaces so she can safely use her mobility aids - as I am sure you can relate. So a ticket when parked lawfully.
After going to the police and complaining and being told it was a completely different department, they took photos of the evidence and the ticket and told me not to worry. If a ticket was coming it would be less than a month they told me. That was in May - no ticket yet.
All just to say, things aren't all they seem to be.
But if you can let us know cities and venues there are loads of locals on here who will help.
Good luck. I'm with you.