Interesting concept
Chesskers- Chess + Checkers Variant
I've never seen an online version of this variant, not surprising since this specific variation is one I invented.
Hey this is my version of chess + checkers hybrid. I was checking to see if anyone else put checker pieces on the 3rd row and found this post because AI told me you were one of the only people to do this. My version there's 4 checker pieces on the 3rd row and the checker pieces can capture optionally. Checker pieces can promote to a checker's king, and they are allowed to do jump more than once if they are able to capture another piece.

There are a few chess + checkers hybrids out there. Checkers pieces are actually pretty strong, but it varies massively depending on the board setup.
Hey this is my version of chess + checkers hybrid. I was checking to see if anyone else put checker pieces on the 3rd row and found this post because AI told me you were one of the only people to do this. My version there's 4 checker pieces on the 3rd row and the checker pieces can capture optionally. Checker pieces can promote to a checker's king, and they are allowed to do jump more than once if they are able to capture another piece.
The version I made up looks exactly like yours, but the Pawns directly behind the Checkers were removed.
I recently tried playing a game of chess with checkers pieces added. It really added a lot of thought to the game especially with the "mandatory takes" rule for checkers pieces.
After trying it out I looked to see if a similar chess variant existed -- it did -- but not quite the way I set it up. I found it interesting. You might find it fun to try out over the board.
Setup:
Back rank is set up standard for chess pieces.
White/Red checkers are put on the black squares on 2nd and 3rd rank.
Black checkers are put on the black squares on 6th and 7th rank.
White pawns are put on the white squares on 2nd and 3rd rank.
Black pawns are put on the white squares on 6th and 7th rank.
If players play 2 games they change colors for the second game. If they play 4 games, the checkers are placed on white squares while pawns go on the the black squares for the 3rd and 4th games and players swap colors every other game.
Rules
Chess pieces move the same as they do in standard chess EXCEPT that pawns may not move two spaces on their first move--even the ones starting on the 2nd or 7th rank (and so en passant is a moot issue). Chess pieces do not have a mandatory take rule. Chess pieces move to occupy the square of the piece they are taking whether they are a chess piece or a checker.
Checkers pieces move the same in standard checkers.
*If there is a choice of ways to take a piece threatened by a checker including chess and checkers pieces, a player can choose to take either with the checker or a chess piece. However, if there is a piece that can be taken by a checker and a piece that can only be taken by a chess piece, the piece that can be taken by a checker must be taken.
Rule Changes from Chess
1. Black always goes first. It's only fair. White has had the advantage for years.
2. If a player has no legal move, they lose instead of stalemating (as in checkers).