I like what they have done with Martial Arts but what about other kinds of martial sports, such as fencing and Kendo? Would it be possible to convert or make a system or set of maneuvers covering these sports.
Like you spend years of mastering the essentials of martial arts, so do you with any other kind of sport, and you learn maneuvers as you go.
I have tried to cover Kendo (could be wrong on the name)´and fencing using CC as a guide, but I do not know if it is an acceptable thing.

My questions are; would it be possible and do anyone have ideas concerning this subject?

Yes. You take a Martial Arts, see, and read the rules, and buy Maneuvers you can use with your weapon category of choice. Maybe not strictly accurate, but it makes you a more well-rounded person overall.

I've done both fencing (a lot) and Kendo(a few times) the skills in both of those would just go under sword skills not martial arts.

I've done it, with help from a friend who has trained Kendo and is currently training Iaido (as well as very hard version Aikido and with a background in other martial arts):

IAIDO (Kendo)

Advantages: The iaido practicioner receives just a +2 TN for Called Shots, instead of the usual +4, and they receive 1 extra dice when using the Zoning manuever.
Disadvantages: It is impossible to use subduing combat with iaido, and the swordfighter looses 2 dice when using the Full Defense option.
Maneuvers: Disorient, Evasion, Focus Strength, Focus Will, Full Offense, Herding, Kip-up, Multi-strike, Zoning.

You can do similar things for any weapon-based 'matrial art'. I did an elven fencing skill using these rules for a hibernated ED Swordmaster one time as well.