App Version: 72.0.3626.31 Beta
iOS Version: 11.4.1, 12.1.1, 12.1.3 beta#2
Device: iPhone and iPad                                                                                                                                                                                                                                                                  

Steps to reproduce:
1.  Set the device region to ‘United States’ and launch chrome
2.  Load duckduckgo.com and search with any keyword
3.  Go to Settings>Search Engine
4.  Select duckduckgo.com as a default search engine
5.  Go to device settings and change the region from ‘United States’ to ‘India’
6.  Launch chrome and go to settings>Search Engine

Observed results:
Notice that custom search engines are removed

Expected results:
Custom search engine shouldn’t be removed

Number of times you were able to reproduce: 5/5
Bug reproducible after clean install: Yes
Bug reproducible after clearing cache and cookies: Yes
Bug reproducible on Chrome Mobile on Chrome Desktop: Not tested
Bug reproducible on Chrome Mobile on Android: Not tested
Bug reproducible on Safari/Firefox: Firefox: NA, Safari: NA
Bug reproducible on current stable build (App Version, iOS Version): No on M71 (Feature is available from M72)
Bug reproducible on the current beta channel build (App Version, iOS Version): Yes on M72 Beta

Link to Video:
https://drive.google.com/file/d/19WNm47zWbSALjS-3lnfNoA84p6KbCk5s/view?usp=sharing