I suggest that altcoin wallet is Ethereum, because there are also many projects that ask for Ethereum address to receive the gift, but you also have to be careful when looking for Ethereum because many of you do phishing where, the key you have to be careful. This is the original link from ethereum
https://WWW.MYETHERWALLET.COM/what coins can i store on etherwallet?
i checked on their website but couldnt find any info about that.