I have seen two chapels in which a layman read the epistle and gospel from a lectern in English while the priest read the epistle and gospel at the altar. Both chapels were independent chapels not affiliated, to my knowledge, with any particular group.
Whether or not this was "legal" or not, I don't know. I can only attest that I've seen it done.
Since the priest was at the Altar, we can assume that this was during Mass. If so, that's an abuse.
Yes. The priest is saying the epistle and gospel during Mass while a layman read the epistle and Gospel from a lectern. When both were done with the Gospel, the layman went back to a pew and the priest moved the Missal, took the ...maniple (?) ... off his arm, laid it on the Missal, and went to the lectern and gave his sermon. At one of the chapels, the priest was not a native English speaker and his sermon was very difficult to understand.
As I said, all I am doing here is attesting to having seen this at a traditional Mass not affiliated with a diocese.
By the way, at the diocesan indult service on Good Friday each year, all three men who chant the Passion from the Gospel are laymen. When the FSSP was in town, they used to have a layman (who was thinking about going to the FSSP seminary) perform the parts assigned to the deacon at a high Mass. Again, I don't know if any of this is "legal", just that I have personally seen it done.