A recent render for the upcoming Sony WF-1000XM4, courtesy of Roland Quandt shows a major redesign and offers a more compact case compared to the current XM3 model. The charging case also looks a bit smaller. The designs for the earbuds along with the metallic finish are shared by both color options.
The battery system has been upgraded in which case each bud in the WF-1000XM4 will be charged at 140mA instead of the 120mA that the current model has. There will be a wireless charging system as well. As for other features, it retains its replaceable soft tips while active noise cancellation is also present. This is described in its FCC documents which have previously been updated and showed that an early June announcement will be made.