Hardcode subtitles with VLC

Open VLC
Select Media > Stream (or CTRL+S by default)
Click +Add… to add your video file
Tick the Use a subtitle file box and choose your .SRT file with Browse…
Click Stream
Verify the Source is correct on the next window and then click Next
Choose a destination file using the Add button while selecting File from the dropdown menu (add .mp4 to your file name) and click Next
Activate Transcoding should be ticked by default, choose your profile (Default H.264 + MP3).
Select the Options button of the selected profile (default icon is a wrench)
Go to the Subtitles tab and tick the Subtitles box and the Overlay subtitles on the video box
Save and then click Next
On the Option Setup page click Stream

Note that you must close VLC once stream is over to complete the file before reading it on a media player.

Options & Video Quality

While H264/MOV profile is selected, you have different options to choose video quality. You can either set a bitrate or a number between 1 and 100 for 'Video Quality'. The lower the number, the higher the quality.

For Chorée Hardcoded subtitles, I used 20 as an equivalent to video quality 23 from Kdenlive. The file size was nearly the same.