I asked the lead Vechain dev about the lack stress testing and I pointed out there's no tx. He said that the stress testing is not for this update.
The P0A2.0 testnet is the alpha. Meaning the code is still unfinished. No point in doing formal stress testing when the code is unfinished.
You can see there's regular development activity on the P0A2.0 [Github](https://github.com/vechain/thor/commits/vip-193-preview) branch. The branch is for VIP-193 , I think they have yet to start implementing VIP-200. [VIP-193](https://github.com/vechain/VIPs/blob/master/vips/VIP-193.md) = committee, [VIP-200](https://github.com/vechain/VIPs/blob/master/vips/VIP-200.md) = block finality.
When the code is mature enough it will be pushed to the official/regular testnet which can be seen as the beta. At that point you should start seeing the stress testing. Based on the tests, bugs will be found and fixed. When all that's done, they'll put the vote up for all stakeholders to vote on pushing P0A2.0 to mainnet.