Having been to all these parks, I think you’re trying to do too much. We live in Portugal now, for the last 3 1/2 years, so have experienced traveling around Europe.
I would absolutely skip Energylandia in Poland, in favor of spending a little bit extra time in the Netherlands or Germany. Tripsdrill and/or Plopsaland Deutschland would work better.
Efteling is a 2-day park, as is Phantasialand if you want to enjoy them. Be aware that traffic in Paris, Netherlands and Germany can be VERY heavy at times, even outside of rush hour. On recent trips by ACE Europe, our drive times were at least 50% longer than what Google said. I would personally never want a car in Paris. Instead, rent a car on your way out of town from the airport.
If it were my trip:
fly to Paris, take the train into central Paris and stay overnight. Force yourself to stay up as late as possible.
day 1: recover from jetlag, walk around central Paris, stay overnight in Paris.
Day 2: pick up rental car, drive to Parc Asterix and stay there.
Day 3: Drive to Plopsaland Belgium and stay there.
Day 4: Drive to Walibi Belgium, stay nearby.
Day 5: Drive to Efteling, and stay there.
Day 6: Efteling
Day 7: drive to Phantasialand, stay at a park hotel.
Day 8: morning Phantasialand, drive to Tripsdrill, stay nearby.
Day 9: drive to Europa-Park, stay at a park hotel
Day 10: Europa-Park
Day 11: Drive to Nigloaland, stay nearby
Day 12: Back to CGD to fly out
For more days, consider:
Extra day in Paris, visit the cute amusement park Jardin d’Aclimatation.
Staying in Brussels between Plopsaland and Walibi.
Add a day in Cologne near Phantasialand.
In Belgium add Bobbejaaland and/or in Netherlands add Toverland, at least 1/2 day each.
In Germany add Plopsaland Deutschland, at least 1/2 day.
I’m not aware you can bring food into parks, but security is much less strict…because…well, no guns (really).
Also, be aware that drink cups are reusable and recyclable, so don’t throw them out. Take them back to a counter for a euro refund, or keep as a souvenir. Food and drinks at European theme parks are far more reasonable than at American theme parks, as is park admission. The price of food and drinks all includes tax, and a table service 10% tip is more than enough.
Where costs will really get you, though, is the price of gasoline, which is upwards of $10 a gallon now! (Thanks to the “war“.)