As topic mentioned, is it possible to use ECG App in Malaysia even though the Apple Watch bought in ECG ENABLED Country?

Yes

I've changed the region but still shows up ECG app is not available in your region, any idea?

You need to enable it in SG first

If i didnt do enabling ECG in SG but i brought it back to MY only do it so any solution for this? Or i still need to go back to SG to enable it?

No other known solution

Naik HSR, when it stops in SG you activate it....

need to use sg telco sim to activate or no?
or as long as we connected to sg wifi?

don't think you need sg telco. maybe sg wifi

See my review in apple watch 5 thread. I managed to get ECG running successfully by setting up in msia on SG unit

How to see your review. New to this platform. Can you share any link?

Yes please, share the link? Thank you!

You need to buy from SG and activate at SG.
Phone have to connect to SG’s telco like M1, Singtel

So once that’s activated, do we need a continued subscription?

It is a hardware + software function. No need subscribe.

Just like camera. Can take photo

No need.

Thank you! In that case, I might try to get it activated since I'm here in Singapore