We know exactly why he absorbed them, it was so he could use their strength to attain the Time Power Unleashed transformation. That's all he does with them.
In regards to them sharing some of the same abilities, keep in mind that abilities like Draw and especially Super Ki Blast are very common in Heroes, and he had both before absorbing the Demon Gods.
Okay True
What your saying does have some Validity. But regardless the Situation is still gonna be very Iffy.
Here's my reasoning:
In Dragon Ball Media in General, Magical absorption has always
ALWAYS resulted in the absorbed target's abilities being used by the absorber. And this result of Magical absorption has
VERY CONSISTENT. It's present within the Animes ( Z, GT & Super ) and within the games as well. A few notable examples are: Majin Buu, Omega Shenron, Naturon Shenron, Moro, Majuub and Multiple other Instances across games Xenoverse, Fusions & Heroes.
There has never been any moment in the animes in which a character wasn't magically absorbed and it didn't result in the character being able to use their powers (at least to my knowledge anyways) making the applications of magical absorption very consistent and implications of Mechikabura being able to use their powers justified.
One more thing, is the character is general. The team behind Mechikabura's character & power obviously designed him to be overpowered and broken, so assuming that Mechi would be able to use their powers isn't to far off. Plus given his character and nature in general since he's very inception, it's clear he wasn't designed to be a fair fight, for crying out loud he had to be beaten by sealing and the seal itself is clutch as it had to formed by using the power of God, of Light, of Darkness and of Time all of which could only be acheived by sworn enemies working together..
Finally, im aware that he STILL HAS NOT USED THEIR POWERS IN CANON, but given everything i've explained i do believe it is as least posssible. So if anything you could just make another section in his abilities profile for those powers he could potentially use. Maybe not in character but potentially all the same
Thank You