Logic Masters Deutschland e.V.

Special Thanks
Thank you to palpot for setting this puzzle with me. We both really hope you enjoy it.

Inspiration for this constraint comes from Threenity by my Dutch Flat Mates co-star GoodCity; with "Easy as 369" used in that puzzle, originally suggested for a setting challenge by damasosos92.

We have had to adapt that constraint slightly, to resolve all digits, and I was surprised to learn there is already an "Easy as ABC" tag on LMD; although a quick browse suggests I may be misusing that tag... or maybe this is the beginning of a puzzle evolution! - haha.

Previous Dutch Flat Mate Puzzles
This has been a weekly series since '18 Oct 23'. Here is a spreadsheet link for all the previous puzzles in the series, which also has a few teasers for upcoming constraints/guest setters in the series (subject to change).

This alternative link offers a limited LMD search for Dutch Flat Mates.

To play the puzzle, please click the image:

Initial Setter Difficulty: 2.5 / 5

Normal Sudoku rules apply
Place the digits 1-9 so that they do not repeat in any row, column, or 3x3 box.

Dutch Flats
Every 5 in the grid must have a '1' directly above it or a '9' directly below it. It may have both, but it doesn't need both.

Easy as ABC
Clues outside the grid indicate which digit of that modular set is seen first in the respective row or column. {1,4,7}, {2,5,8}, or {3,6,9}

Hint to start

If your eyes aren't immediately drawn to the 8s, I probably can't help you further - lol - They are powerful deep into the solve, but the first issue is a happy 5 in Row 9.
Row 6 digits, particularly the 2, starts to break the back of the puzzle.