Clock should be fine with the stock games and most hacks. I can't rule out there being some weird and wonderful clock altering hack that colours outside the lines though.
Basically all flash carts that are not a supercard should work fine with basically all patches, give or take some issues with clock patches (but again as the EZO has a clock then yeah). It is not like the NES, GB/GBC, SNES and N64 where you have certain games need certain hardware that only certain carts support*, people making patches to support weak emulators**, high res texture stuff, people adapting games to use extra hardware or the usual sorts of things that break them.
*most of those devices have carts that occasionally have specialist onboard hardware that increases the power of the system, or does something in an odd way. The GBA does not really have this outside of the clock stuff mentioned, tilt sensor, solar sensor and maybe the GBA video.
https://gbatemp.net/threads/buying-a-gba-flash-cart-in-2013.341203/page-18#post-4756995 is my usual list of troubled games.
**I have helped one or two people over the years when they were making their patch and they did something wrong that resulted in it working in an emulator but failing in hardware. Most times it is a simple compression mismatch which you could possibly learn to fix.
