Instrument currency/IPC is category specific, not class specific.
So as long as you're legal to fly the ASEL, by virtue of having a CFI/PIC on board you can do an IPC.
That's for an IPC, obviously not for initial IR checkride in AMEL... the checkride has AMEL specific tasks.
If you maintain currency in a ASEL that applies to AMEL and vice versa.