Yes, with one rule that is not negotiable: never split the front three.
Left, centre and right carry the film's front soundstage, and sounds pan across them constantly. If the centre is voiced differently from the pair beside it, every pan has an audible seam: a car crossing the screen changes tone halfway, a voice moves off-centre and shifts character. Same brand and, ideally, same series across the front is what makes those three behave like one instrument. Different tweeters, different crossover slopes and different cabinet resonances all show up right where you are looking.
Surrounds have more freedom. They mostly carry ambience and effects, and the material is less continuous with the front, so a different brand or series is acceptable and matching is nice rather than critical. I would still try to keep them tonally similar; a very bright surround pair behind a warm front three draws attention to itself in a way that is fatiguing.
Heights sit in between. Same brand is preferred, but up there placement and dispersion matter more than family resemblance. An in-ceiling from another brand aimed correctly beats a matching upfiring module aimed at nothing.
Subwoofers are brand-independent. A sub only works below the crossover, typically 80 Hz, where there is no timbre to match, so pick the best sub for the room and the budget and ignore the badge. Nobody has ever picked out the brand of a subwoofer from a bass note.
Where does the rule stop mattering? Music-only stereo systems: two speakers, no panning across a centre, so match the pair and you are done. And older systems where the original series is discontinued: then the closest current series from the same brand is usually a safer bet than a different brand entirely, but send us the models before assuming.
Short version: never split the front three, be pragmatic everywhere else. If you already own part of a system and want to grow it, tell us what you have and I will say what fits and what will fight it.
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