GPAW has a large set of PAW setups (updated in 2016) for elements from H to Rn, excluding lanthanides, actinides, and radioactive elements. One can generate new setups with a PAW generating build-in tool and their own risk. One can use optimized norm-conserving Vanderbilt SG15 pseudopotentials (updated in 2017) or norm-conserving Hartwigsen-Goedecker-Hutter HGH pseudopotentials (see also GPAW intro) or even JTH pseudopotentials from ABINIT. There are even more setups, including f-elements, listed on the QE webpage. The great thing about these setups is that they use a similar format – either xml or upf. Apparently, GPAW can read both formats, although there is no relevant documentation. So, there are many ways to run calculations with elements that are missing in the GPAW default setups set. QuantumATK webpage provides an overview of pseudopotentials and even suggests mixing them. I hope that in the future, these and new PAWs will be gathered together like basis sets at the basis sets exchange portal.

P.S. Interesting https://esl.cecam.org/data/ and https://molmod.ugent.be/deltacodesdft