Maybe not. Shopee is known for very cheap items and I doubt there will be people wanting to pay in bitcoin. And is bitcoin that big in south east asia? But I thought that if bitcoin gets accepted in shopee, it will be a huge sign of adoption.
Businesses accept Bitcoin mainly based on customers' demands. It will be ideal for e-shopping firms that are located in a country with high crypto awareness and adoption to accept cryptocurrencies as an alternative source of payment. I don't know the level of crypto adoption in Southern Asia, but crypto payment options are not popular in my location because of low adoption.
Before discussing making Bitcoin a payment option in a location, it will also be important to check the laws of the country. Whether the government allows the use of crypto for payments should be considered first.