Hi Harshitha Ramesh - Thanks for reaching out over Q&A Forum.
From the effect standpoint, if there are any calls that are hitting storage on lower version such as TlS1.0 or TLS 1.1, after setting the min TLS version as TLS 1.2 on the account, those calls shall tend to fail. If the calls are hitting on TLS1.2 already, then it should not affect.
There is no cost involved in making the changes and also no downtime required as it a configuration change.
To ensure there is no connectivity issue, you can check for current version of calls hitting the storage and plan ahead.
https://learn.microsoft.com/en-us/azure/storage/blobs/monitor-blob-storage?tabs=azure-portal
Hope the above answer helps! Please let us know do you have any further queries.
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