Agfa used to make a paper developer called Metinol which was recommended for this sort of work because it was slower working and gave more time to even out unevenness. I made a tray from a timber frame and a chipboard base and placed in it a length of plastic film, enough to make a makeshift tray. It has to be able to be lifted and emptied and then a stop (might stop staining) then fixer. The amount of liquid doesn't have to be much at all. In my experience concentrated paper developer can be more prone to staining. I would do it in a cool location if possible to slow down development and maybe a tendency of the developer to oxidise.
Metinol was a metol-only developer. It might produce slightly lower than normal contrast: I don't remember because in those days my negs were overdeveloped anyway. This was in about 1972.
It's worth having a look at Lloyd Erlick's recommendations for single tray processing:
It's an old site but some things don't change(!)
edit: There are formulas on the www for "Metinol U" but mine was definitely just "Metinol". The formulas are contradictory: some have hydroquinone, and some only metol. Agfa were odd with names: remember Rodinal and Rodinal Special which were totally different. I'm sure I remember Metinol being metol only.
edit2: Metinol was actually metol hydroquinone developer according to a photo of the packet on Google. My memory must have been playing tricks on me (forgiveable at my age).