3GPP 24.501 v20.0.0 — the document's own text
5.1.4.1 General
Taught in 4. Inside TS 24.501, the document at the centre (CT1 — the group that writes what your phone says, overview).
If both 5GMM and EMM are enabled, a UE, operating in single-registration mode, shall maintain one common registration for 5GMM for 3GPP access and EMM.
Coordination between 5GMM for 3GPP access and EMM for a UE, which is capable of N1 mode and S1 mode and operates in dual-registration mode, is not needed, except as specified in clause 4.8.3.
The coordination between 5GMM for 3GPP access and EMM in clauses 5.1.4.2 and 5.1.4.3 only applies to the UEs operating in single-registration mode.
Regarding the coordination of "SIM/USIM considered invalid" and "USIM considered invalid for 5GS services" between the various mobility management entities see clause 5.1.5.