Many popular addons have been ported to C3. Don't know about Cranberrygame addons though, you will need to research. Also, there is Plugin Converter which you can try, but it only supports runtime 2.
If you can't find Cranberrygame addons for C3, the best option would be removing them from your project, then migrate to C3 and find alternative plugins/addons. For example, there is now a native sharing plugin in C3.
Also, take a look at this massive collection by ChadoriReborn, it's not free, but well worth the asking price:
chadorirebornxd.itch.io/construct-master-collection
construct.net/en/forum/construct-3/plugin-sdk-10/construct-master-collection-139046