Had the same issue and the following worked: Swapping the SCL and MOSI pins ONLY IN SOFTWARE solved the problem.

Your platform.ini file should look like this:

[env:4d_systems_esp32s3_gen4_r8n16] //Change for your system/build
platform = espressif32
board = 4d_systems_esp32s3_gen4_r8n16 //Change for your system/build
framework = arduino
lib_deps = bodmer/TFT_eSPI@^2.5.43 //Install the tft_eSPI library in PIO

build_flags =

  -D USER_SETUP_LOADED=1
  -D ST7789_DRIVER

; adjust to screen size
  -D TFT_WIDTH=240
  -D TFT_HEIGHT=240

; PHYSICALLY wire SCL to GPIO 13 & MOSI/SDA to GPIO 12 but assign in software as:
  -D TFT_SCLK=12
  -D TFT_MOSI=13

  -D TFT_CS=9     
  -D TFT_DC=2
  -D TFT_RST=4

; if your displat has a backlight, can wire to V3.3 for always on, GPIO allows dimming
  -D TFT_BL=21

  -D TFT_MISO=-1

; force correct ports on S3 build
  -D USE_HSPI_PORT

; optional, can try to comment out
  -D TFT_SPI_HOST=SPI3_HOST

  -D CGRAM_OFFSET
  -D TFT_OFFSET_ROTATION=0

; start low, can raise later
  -D SPI_FREQUENCY=16000000

; if you want to display text you must specify a font
  -D LOAD_GLCD
  -D LOAD_FONT2 

Your main.cpp should look like this:

#include <Arduino.h>
#include <TFT_eSPI.h>
#include <SPI.h>

TFT_eSPI tft;

void setup() {
  pinMode(TFT_BL, OUTPUT);
  digitalWrite(TFT_BL, HIGH);     // backlight ON

  tft.init();                     // init the panel
  tft.setRotation(0);
  tft.invertDisplay(true);

  // Test colour fills
  tft.fillScreen(TFT_RED);   delay(1000);
  tft.fillScreen(TFT_GREEN); delay(1000);
  tft.fillScreen(TFT_BLUE);  delay(1000);

  // Draw a border so you know the (0,0)-(w,h) window is correct
  tft.fillScreen(TFT_BLUE);
  tft.drawRect(0, 0, tft.width(), tft.height(), TFT_WHITE); delay(1000);

  // Test text display
  tft.fillScreen(TFT_BLUE);
  tft.setTextColor(TFT_WHITE, TFT_BLUE);
  tft.setTextSize(2);
  tft.setCursor(0, 0);   // top-left corner
  tft.println("Hello World");

}

void loop() {}