The charger and cable are the only things that matter. The travel adapter doesn't do anything except conduct electricity, kind of like extending the cord by an inch.

I'm 99% positive the travel adapter can handle the amps the charger is putting out. It's probably designed to handle way more. But you can use THIS APP to check that the same amps are going to your phone with and without the travel adapter.

Remember, the most common problem is using cheap cables. Lots of cables can't handle the amps that the charger can put out. For example, your charger could put out 2 amps, or 2000 milliamps, but the cable might only be able to handle 500 milliamps. Even this wouldn't damage your phone, it would just charge slower.

Read the fine print on the back of your charger and see what its output is. The output amps should somewhat match what the app says. It won't be exact but it will be in the general vicinity.

It's a smart question to ask. Let me know if you need anything else.