At the moment, there isn't a 5520 equivalent in Europe, or any of the newer models with the 4 range transmission for that matter. Not sure when those will get here. Currently we have the 5025 and the 6225. The 5025 uses the A2300 engine naturally aspired, while the 6225 uses the same A2300 but the turbocharged one.
In 2022, the new Stage V emissions will be applied in Europe and all new tractor have to compliant to Stage V, which most already are as most manufacturers have been making the change in 2021. This actually resulted on a lot of discontinued models, specially on Branson with only 3 models above 25 HP. I'm sure they will release more models once they get the older models up to the new Stage V spec.
This new Stage V requirement, is basically the same as the US now. Emissions stuff required on offroad equipment above 25HP, while before it was only required above 50HP. The later part of this paragraph is important be this means that the 5025 had a simple muffler, but being naturally aspired, it won't fit on your tractor. The other models 5825 (disconntinued) and the 6225, both have turbo, however, being that those are above 50HP, they have the DPF and not a muffler.
Maybe things are different in Australia on the emissions requirements, and there is a model there with A2300 turbo'd engine and a muffler instead of the DPF and a dealer is willing to ship the muffler to you. Otherwise, as Slowpoke Slim explained, it's very easy to retrofit one.
Another thing to consider, is that on the 2021 US models, the data logger has some of the engine wiring hardness integrated into it. So if you unplug the datalogger, I believe you lose the temperature indicator at the dash, accordingly to someone who tried it on this thread. We're waiting on the service manual to be available so we can investigate this further.