Although I'm unable to answer the question, I think it can define it more precisely. Is about with the help of which modal verbs you can tell what another person said. They have it in German and that is, I think, what the question means - whether there is such a construction in English. For example: Direct speech: "I am tired", said the teacher. Indirect speech would be
"The teacher said he would be tired" is perfectly okay in English. I don't know whether or not this is specifically related to reported speech, however. This is an example of "future in past" tense - describing a prediction made in the past.
Konstantin, you're referring to the Conditional with your German example. Indirect speech in German works differently as the Conjunctive has to be used in formal German, which however, can be replaced by the Conditional (would+infinitive).
In English, the tenses have to be shiftes back from direct to indirect spe