In SEPA payments, according to Annex 3 of this document, only characters of the limited SWIFT Latin characters set are allowed:

• a b c d e f g h i j k l m n o p q r s t u v w x y z
  
• A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
  
• 0 1 2 3 4 5 6 7 8 9
  
• ' : ? , - ( + . ) / |