Exchanging crypto is still allowed here, you're just
not allowed to make any payment with crypto. The biggest Indonesian exchange is indodax.com so that's my recommendation. However, you need to comply with their KYC procedure before making fiat (IDR) transaction.
Terima kasih!
Is it possible / safe to use coinbase.com, binance and kucoin too?
or should i stick to the local exchanges?
You can use all available exchange if you want to trade your Bitcoin, but if you want to cash out your bitcoin and you cant do KYC ( because Indodax require Indonesian ID ) you can use LUNO. Luno have low fee and easy to use.
BTW trading at coinbase.com is not available in Indonesia