Do I need a hardware mixer?

Spinning dance music. Using Traktor on laptop. Wanting to spend my money wisely. I have a few midi controllers and a Scarlett 2i4. The Kontrol Z2 went on sale which is tempting but for the same money I could pick up two X1s + maybe an Audio 6 interface or something similar. Lot's of options. My thinking is if the clubs have mixers then I wont be bringing my own obviously and there is no point integrating cool features of a particular mixer into my workflow if I wont be able to use them in the clubs anyhow. So for all intensive purposes, until I got money to burn, if I need to practise with external mixing I could just get a cheap DJ mixer or rent one.

Just wanting opinions and to see if my logic is sound (pun).

Not sure I agree with your logic to be honest. Ultimately you have a home set up for three reasons, building a set, practice and practice.

It sounds like you want to play out and this means playing with your own kit of playing on a clubs install. If you get a club gig they would expect you to be instant on kit familiarisation, no messing just jump up and play. OK, mixers have differences on effects but the fundamentals of channels and faders are the same on all of them, practice on your own mixer will keep you sharp.

Most people don't start off straight with a club residency; its a slog that starts with house parties, pubs, small venues and increasing to bigger venues as you get a rep behind you. This is a passage of rights which is good for you, to go on that journey you pretty much need your own kit.

Think carefully about where you want to go here, whatever you buy, but something that will be expandable and can be used in conjunction with more gear as you build your set up. Z2 is pretty good for this as X1 & F1 integration is simple and spot on.

Are you aiming for timecode or just a couple of X1s? The 2i4 will be fine for 2 external decks, or for internal mixing.

Not using timecode.