There is no direct conversion for this in Blender, but you can do this kind of thing using the Video sequencer/editor in the video editing tab of blender. First you open the video editing tab:
And then press SHFT+A to open a dropdown menu that will give you the option to add a movie. Press this, and Blender will take you to a browser. Select the movie (.avi) ...
Speeding up the video framerate (which is what I believe you mean by video speed) can be done the same way in 2.8 as it can be in 2.79 and before. In the render settings, switch the default 24 FPS to whatever is faster than that. It should speed up the video speed.
Using the Parallel Render add-on will allow you to render, from the Blender Render panel, using all cores, which will give you a speed-up: https://github.com/elmopl/ktba/blob/master/scripts/addons/parallel_render.py
Another thing which may speed up export is to change the colorspace from Filmic to Standard.
I am not aware of any way to do that by default. That's why wrote a little add-on for you.
The add-on allows you to create a list of paths that the file should be saved to. Then every time a render is written to disk it is automatically copied to the specified paths.
The add-on can be downloaded here: https://github.com/oweissbarth/blender_multisave/...
I figured it out thanks to this question:
First, you want to look for the 'window selector' icon, and click it, and choose the 'Video Sequence Editor' option:
Next, if you don't immediately see the video preview, you want to click a button on the bottom of that window that has a red-and-white checkerboard pattern, that will switch the window to be a video ...
You can use HandBreak to transcode your footage into the needed framerate, or you could render your animation alone and edit it together in a dedicated video editor like Premier, Kdenlive, etc. Blender can be used to transcode but its not the most convenient way.
You can revert back to Blender 2.7X keymap in the Preferences
Edit: Sorry I didn't see the part about more than one frame at a time. My bad!
If you wish to stick with the current keymap though, you can add another keybind for that.
Head back over to the Preferences tab, go to the Keymap option, and scroll down until you find the Frames dropdown menu.