Hello Diane,
I'm afraid it would be extremely difficult to backport the changes from Moodle 3.6 into Moodle 3.5.
Although you only want the features of the new blocks, many of these features rely on other new APIs and functionality not present in 3.5.
It may be worth considering switching to Moodle 3.6 which does have these features already. It will be supported until May 2020, which roughly coincides with the date of the next LTS release. Although there will be less of a date crossover than using Moodle 3.5, this may be sufficient for your purposes.
Best wishes,
Andrew