The first sentence is grammatically correct; the second is not.
The idea is: It is considered that + Repin painted this picture (active)/This picture was painted by Repin (passive) -->
It is considered that this picture was painted by Repin.
Using "it is considered that" requires a change of verb tense as the structure is "indirect".
(See the rules for indirect/reported speech here: https://www.tesol-direct.com/tesol-resources/english-grammar-guide/reported-speech/ ).
February 23, 2017
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