Most of the recommendations I found on this sub is for the Nvidia Shield TV. Unfortunately, in the only store where I found it in my country, it costs the equivalent of $450 , which is way too expensive (that's how much the TV cost). I can order it through amazon.de for around 200 euro, but it's still over my budget.
I wasn't impressed by the Xiaomi Mi Box.. it has only 1 USB port, and no Ethernet connection. It supports 4k, but might struggle in some cases.
Is there any good alternative to these 2?
Not if you want Android TV. The only alternatives would be Amazon's devices or Apple TV.
Edit Thanks for the downvotes...the OP asked for good alternatives.