I think for a dishwasher to be considered portable it would have to be too small to be considered useful. The smallest dishwashers I know of are countertop units. Usually they fit two sets of dishes, tops, so a single-household will have to run it at least every day.
But even they are too big to be carried around comfortably. You might consider them luggable.

Maximus makes some tabletop dishwashers.

Countertop dishwashers cost around PhP20K, depending on the brand. You might want to visit the bigger SM department stores to physically check the "portability", size, and weight. I think they only carry the Hanabishi brand.

Lazada can have lower prices during the sale season, though, so you might want to consider waiting to get some discount. Lazada has more brand options, too.

As for usefulness, you can't wash some items with a dishwasher. Some plastics can deform due to the heat. If the detergent is too abrasive, it can ruin non-stick pots and pans. You can't use Joy. Also, smaller dishwashers can't accommodate fullsize dinner plates. You also might want to test fit some dishes when you physically check one.

I've been using the Maximus Mini Dishwasher model for 2yrs now, though bought it on sale at around PhP15k. https://www.thegreatest.ph/store/p12/MAX-004M.html

Soap: Seventh Generation Dishwasher Detergent Powder

As someone that hates washing dishes, this appliance is a lifechanger.

Caveat: We only use the Rapid option (runs for 30mins. Does not include the drying option) then air dry after. Super tagal ng Eco/intense options for me, I think they run for more than 2hours so feel ko sayang sa kuryente eh natutuyo din naman at the same time via air dry.

Pros:

• very effective in removing sebo in plastic dishes
• Can accomodate dishes used for 1 or 2 meals for a small family (excluding cooking utensils)
• Tipid sa tubig kasi 5L lang for a full load
• Tipid din sa soap, kaya tumagal ng half year isang box
• Acts as a drying rack na rin
• Peace and harmony sa household (can't emphasize this enough. Lol)

Cons:

• Need to ensure that your dishes are dishwasher safe, so byebye sa cute plates from Daiso. We had to swap them with Ikea Kalas.
• Hindi na kame gumagamit ng full sized dinner plates since bulky sya masyado. Sa mangkok na lang kame kumakain
• Mugs lang din ang drinkware namen dahil bulky kasi normal glasses.
• Limited din lalagyan ng kubyertos, so minsan manual din sya hinuhugasan.
• Sa The Marketplace / online lang available yung dishwasher soap.
• Smallish pots + pan can fit, pero hindi practical kasi sayang yung space

https://havalab.com/products/hava-r01-compact-countertop-dishwasher-google?utm_source=google&utm_medium=cpc&gad=1&gclid=CjwKCAjwzo2mBhAUEiwAf7wjksfgoO0znVxN6NtJxJIxYPH8Zr3KXopRD5TJS1dIXY_hrFCjnjYmhBoChC0QAvD_BwE