The 1, 2 and 5 cent coins of the Euro are copper plated steel. I'm surprised they still use steel, I would have expected copper plated zinc as it's cheaper. Countries like Finland and The Netherlands actually don't even produce coins of 1 and 2 cent anymore (except for sets) as it's too expensive to produce and use. So yes, some countries are already showing their 'attitude' here.
10, 20 and 50 cent should be made of Nordic gold, which should contain 89% copper, 5% zinc, 5% aluminum and 1% tin. These shouldn't be magnetic at all.
Coins of 1 and 2 euro should be magnetic up to some point, as they are partially consisting of nickel, a ferromagnetic metal.
If you want modern 'plastic' coins, then I suggest that you have a look at what Transnistria has to offer. Transnistria is a communist Soviet breakaway republic in Moldova, supported and actively backed by the Russians. They claim to be the first country to have issued coins made of composite (plastic) materials. Do note that their currency is almost worthless in their tiny spot of the world and completely worthless outside it.
Otherwise, German Notgeld had a lot of interesting materials used for coins, including Bakelite, the predecessor of modern-day plastic.