URLs from imported Blogger not matching WordPress URLs

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I have migrated from Blogger to WordPress, but here is one problem.
Blogger url:
Example 1:2010/10/test.html
example 2:2010/9/test.html (here in two different date 2010/10 and 2010/9 we can have same test.html, see below for WordPress)

Like above it was coming in Blogger, but coming to to WordPress:-

WordPress Example 1:2010/10/test.html
WordPress Example 2:2010/9/test1.html (in WordPress I am not able to give the same name as we can see that 2010/9 is different than 2010/10, so we can have test.html in both, but in wordpress it is considering it as duplicate and changing it to test1.html and this is not the case in Blogger)

My concern, this website is famous in Google and and if URL will change, then there is no use of migrating from blogger at the cost of traffic.