Form Field Manager

Tell me how to create fields for multilingual forms? There are two forms of donation: DE-de and EN-en. When creating a field in the DE-de form, it is duplicated in the EN-en form in the DE-de language. I specify Meta Key _de but it is duplicated in the form in which Meta Key _en should be. If you rename the duplicate to Meta Key _en then in the form with Meta Key _de, Meta Key becomes _en. Please help me figure it out.