Hi @juanmolina. Finally I have signed up to lykke. In their platform you can trade lot of cryptos and fiat currencies, including STEEM. However I see there is not much liquidity.
The funny thing is that Lykke is not in the list of coinmarketcap STEEM's market:
The other funny fact is that until now I realized that most STEEM trade volume takes place in Korea (see pair STEEM/KRW in upbit's market)
I hope this can be useful.