Looks like Android 12 will let you use two SIMs on Pixel 4a 5G and Pixel 5 without any trade off
It appears that Android 12 will let you use two SIMs on Google's 5G ready smartphones without any limitation.
Unlike the Google Pixel 3a and later phones, the Pixel 4a 5G and Pixel 5 don't let you take full advantage of the Dual SIM Dual Standby (DSDS) option. This could change with Android 12, reports 9to5Google, citing a Reddit post.
On the Pixel 4a 5G and Pixel 5, if you use two SIMs at the same time, they fall back to 4G networks. To connect to 5G on these phones, you need to turn off the SIM that isn't set to use data temporarily. Your options including removing a card, deleting a profile, or disabling a SIM through the Settings app.
It was earlier believed that Google would enable Dual SIM Dual Standby 5G support via an Android 11 update. A code change posted back in November 2020 to the Android Open Source Project (AOSP) had suggested that Google's new phones would be able to connect to 5G networks in DSDS by December. The February security patch is out now and it does not offer DSDS 5G support.
That's apparently because the functionality is not due to arrive until the next major OS update.
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