https://www.malaysiaairlines.com/us/...ge-access.html
Economy Passengers can pay for access for some time already. Either MYR279 or MYR320 per access depending on one buying online or at the door.
I'm not sure how busy the Regional/Satellite J lounges are these days, though when I used them late last year in the morning and midday, there were sufficient space and it wasn't as busy as those sad Aspire/Escape lounges you see in the UK.
F lounge doesn't get very busy though in my recent experiences, except nearing the time of JL724's departure, which is often filled with JAL Global Club Top-tier Elites