Yes, bunq works but comes with fees.
The original question is not that informative. To be honest, it is more like 98% of all EU-IBANs have the functionality while 2% don't. Hence, it would be good if OP would actually post what the real bottle neck is. Does he need to use 5 accounts each month? Does he need 25 accounts in total? Where is he resident and what fees are acceptable.
In Switzerland, most real banks offer quick and easy opening of new accounts online for no additional fees. In Germany, I am not sure, DKB, Comdirect are︀ not exactly known for many IBANs. UK again is more like Germany, where you can︁ simply open another 10 accounts yourself online. Have you checked with HVB or Volksbank?