SL (SpeakerLink) vs SE (special edition)?

Equalisation - are you asking about boundary settings? If so it’s available on all (?) DSP speakers, legacy/SL/SE, via MSR/IR config.

Meridian owner since 1992
Prime & PSU, Focal Elear headphones, Roon (ROCK 8Gi5 NUC), Explorer 1 & 2, F80. 200/203, various Sonos (via Roon).