My car+tranny has (and is KNOWN for) this issue.
If I shift into 2nd from 1, it makes a clunky noise. When the engine/fluids are still cold it will do this EVERY time and is quite loud.
If I shift from 1 => N => 2, then the noise does not appear.
Shifting from 2 => 3 rarely does it and 3 => 4 even more rare.
Once completely warmed up, it rarely does it, period.
In my case, the cause are the synchros.
The known mitigation is to use some "special" transmission fluid.
I have not changed out my fluid to the special fluid so it keeps making the noise, but it isn't really anything to be worried about unless you are having a hard time putting it into gear. If you are having a hard time putting it into gear, then those synchros are probably messed up and will only get worse and worse, and it would already be too late to do anything about it.
If you are worried it's killing your synchros, you can try to do a fluid change and have a oil analysis done to check for synchro material in your fluid.
You can try double-clutching and see if that helps with the noise.