⭐ Merited by estenity (1)
i saw an option in the wallet about sending and receiving waves to / from a eth-blockchain? since when is this possible ? it a erc-20 adres 
I don't know exactly when it has started but yes, there is a gateway at waves.exchange.
Quote
Users will be able to move the WAVES token between the two blockchains through a gateway launched in the Waves.Exchange client interface. The withdrawal fee will be 2 WAVES and the deposit fee will be 0 WAVES. In order to issue one ERC20 WAVES, users have to lock one WAVES on the Waves blockchain.
https://medium.com/wavesprotocol/waves-issues-erc-20-for-collaboration-with-ethereum-network-122a968e6a09https://medium.com/neutrinoteam/neutrino-ports-into-ethereum-26d9d5750669