Fill in the sudoku on the left so that each column, row, box, and section of the same color contains the numbers 1 to 9. The dots indicate how many numbers in the corresponding row or column of the grid on the right match the solved sudoku on the left. Goodbye!
I used the f-puzzles sudoku setting tool when solving this puzzle (for conflict highlighting and to be able to type my answer into a grid; I can delete this answer if conflict highlighting is not allowed when solving sudoku puzzles). Here is a link to a clean version of the left grid on f-puzzles, if someone else wants to use it to solve this puzzle.
Note that this does not include the second grid (I don't think f-puzzles supports Columbian sudoku constraints), so you will need to have the second grid open separately to use it.
Solution:
Green digits show matching cells, red digits show non-matching cells.
Steps:
I retraced my steps after solving to generate a list of steps, so some pencil marks and/or colors may be missing from these steps:
Step 1:
Identify initial positions matching and conflicting with the grid:
Note: I missed r2c4 here, but corrected it in a later step.
Step 2:
There are two different digits in the unknown cells in row 5 and two matches, so we know that a 2 goes in r5c1 and an 8 goes in r5c2, r5c8, or r5c9. This forces an 8 into cell r6c7 in the center region, which prevents r6c2 from matching, so r6c8 and r6c9 must be the other two matches in row 6:
Step 3:
We can repeat the logic from step 2 to place a 9 in r3c1 and r8c4:
Step 4:
There is only one free cell for a 2 in region 4 (r3c2), and this starts a chain to place the remaining 2s in the grid.
Step 5:
There are three digits and three matches in column 6, so we can find r1c6, r2c6, and r8c6:
Step 6:
The 7 in r8c6 in the previous step starts a chain to place the remaining 7s in the grid:
Step 7:
Continuing on, we can find matches for row 1 and column 1:
Step 8:
There is only 1 spot for a 1 in the green region (top left grey region in screenshot), and we can complete row 4 since r4c8 and r4c9 must match the other grid:
Step 9:
After placing more digits following row/column eliminations, we get here:
From here, we can see that either r8c2 and r9c9 or r8c9 and r9c2 must be the last matched cells. The 5 in r8c1 forces r8c9 and r9c2 to be the last matches, and we can fill in the remaining digits:
