@SrDarkWarrior
Anything from TP-Link should be fine.
From other brands, based on personal experience: TRENDnet TEG-S80g. This is my main 8-port gigabit switch I've been running for years, and about a year with Deco M9 Plus and M5 units connected through it. Very pleased with its performance. All 8 ports utilized, handles everything very well.
General recommendation: avoid D-Link brand, and look for no-frills unmanaged switch. Also, because all Deco units use same protocols for backhaul, if switch works for M9 Plus, it'll work for X20, too.
Switches are briefly discussed in this document, see Q4 and Q5: General questions about Ethernet Backhaul feature on your Deco