Upvote:2
Theoretically no. However their are two threads over on flyertalk discussing exactly this. In the first one, a person claims regularly to pass through airside transit without a boarding pass check in order to reach the lounge. They then use their EVA Diamond card to access the lounge.
The second newer thread contains information from an EVA Lounge Host:
Arriving passengers (*G & RL) would not be allowed to use the EVA Lounge facilities without connecting flight ticket.
This is the most common situation for lounge access unless there is a specific arrivals lounge.
Indeed a later post from someone attempting access in a similar situation states:
made it up through transit security but was flat out denied at the lounge entrance and they wouldn't budge, although I didn't push them to ask management.
Bear in mind that if you do attempt this, you need to get back into the correct arrivals stream to pass through immigration.