Entiendo que has tenido en cuenta lo que indica el propio desarrollador, żno?:
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ROM AND KERNEL FEATURES [22-Jan-2020]
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-GOOGLE PAY SHOULD WORK. USE MAGISK TO HIDE ROOT. U may need Gpay enabler
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How to get the Gpay back...
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1-https://pastebin.com/HKV7cj7H
2-https://forum.xda-developers.com/smartwatch/other-smartwatches/rom-kernel-t3821013/page172
3-https://www.youtube.com/watch?v=UKxGfNxRjo4&t=320s
4-https://forum.xda-developers.com/showpost.php?p=79637148&postcount=1720