Avec deux listbox

Un autre code fait à l'arrache =D

import tkinter as tk
from tkinter import font as tk_font
import json
SCROLL_WIDTH = 18
LISTBOX_HEIGHT = 12
def players_load(path):
 with open(path) as f:
 return json.load(f)
def player_select(list_box):
 i = list_box.curselection()
 if not i:
 return
 value = list_box.get(i)
 if players_selected[not list_box.id] == value:
 return
 players_selected[list_box.id] = value
 players_label.config(
 text=f'{players_selected[0]} - {players_selected[1]}'
 )
players_selected = {0:'', 1:'',}
players = dict(sorted(players_load('joueurs.json').items()))
list_box_width = max(len(p) for p in players) + 2
window = tk.Tk()
font = tk_font.Font(family='mono', size=18)
frame_box = tk.Frame(window, bg='#000')
frame_box.grid()
left_scroll = tk.Scrollbar(
 frame_box, orient=tk.VERTICAL, width=SCROLL_WIDTH,
)
left_scroll.grid(row=0, column=0, sticky=tk.NSEW,)
left_list = tk.Listbox(
 frame_box,
 font=font,
 width=list_box_width,
 height=LISTBOX_HEIGHT,
 xscrollcommand=left_scroll.set,
 yscrollcommand=left_scroll.set,
)
left_list.grid(row=0, column=1, padx=(10, 5),)
left_scroll.config(command=left_list.yview)
left_list.id = 0 # C'est crade !
right_scroll = tk.Scrollbar(
 frame_box, orient=tk.VERTICAL, width=SCROLL_WIDTH,
)
right_scroll.grid(row=0, column=3, sticky=tk.NSEW,)
right_list = tk.Listbox(
 frame_box,
 font=font,
 width=list_box_width,
 height=LISTBOX_HEIGHT,
 xscrollcommand=right_scroll.set,
 yscrollcommand=right_scroll.set,
)
right_list.grid(row=0, column=2, padx=(5, 10),)
right_scroll.config(command=right_list.yview)
right_list.id = 1 # C'est crado !
players_label = tk.Label(
 frame_box, height=3, font=font, bg='#000', fg='#fff',
)
players_label.grid(row=1, column=0, columnspan=4,)
left_list.insert(0, *players)
right_list.insert(0, *players)
left_list.bind(
 '<<ListboxSelect>>', lambda e: player_select(left_list)
)
right_list.bind(
 '<<ListboxSelect>>', lambda e: player_select(right_list)
)
window.mainloop()

Y a des trucs un peu moches, notamment d'insérer des attributs id aux listbox (permettant de savoir si la sélection courante n'est pas la même que celle de l'autre listbox), il serait préférable de créer une classe dérivée de Listbox et y intégrer un id via un attribut de classe.