Yes, you can combine it in multiple ways! One way is using Sell The Trend for the product research part and Spocket to get access to the US and European dropshipping suppliers. But you can also use Spocket for the US & EU suppliers part and use Sell The Trend to connect your store to AliExpress. (Plus, the research part) I know this can sound a bit complicated, so if you're not sure yet about this, check out this article here. Don't forget that they already have an integration with CJdropshipping in case you were wondering if they can connect to something else than AliExpress.